A story of eco-renovation

A private publication by Malcolm and Betty Crocker.

Freely quotable in any form with acknowledgement to the author.

It is my hope that the details may be used without restraint by those wishing to pioneer eco-renovation in their own homes or professionally.


My Motivation

In January 2006 I was unaware of the serious nature of climate change although I had been studying the deterioration of pastures and the advance of the desert in Kazakhstan.

In February 2006 I joined the BBC Climate Change experiment to add my PCs to the 200,000 others involved in modelling the changes in climate. As a result I became aware that this would threaten the happiness of my grandchildren and deserved serious study.

I enrolled in an Open University Course called Climate Change Modelling and joined a Yahoo Group on the internet called ClimateConcern. The former was very limited in its scope but the latter has provided a mine of valuable information gathered by those far wiser than I. I have been increasingly aware of the seriousness of the problem and the difficulties facing any solutions.

I have formed a WIKI to enable others to co-operate with me to assemble facts and opinions regarding the evidence, outcomes, damage, and possible solutions. I am certain from the past year of studies that the damage is still being underestimated by governments and by the majority of the people in every nation and the prospect of action in time is still remote Please add the facts you have to my climate study Wiki at

The following facets of the problem require urgent attention.

  1. Better scientific measurements of the damage being caused and likely in the future

  2. A better informed press and public

  3. More radical action by governments

  4. Technological advances in renewable energy at breakneck speed.

  5. More case studies that can show what is possible.

I reject the minor savings the individual can make as ineffective and cosmetic, but if they are well documented they can form the basis of future legislation. For example the energy I can save by solar power generation may then be used extravagantly by someone else. However, by documenting my home solar project I can prepare for the promotion of solar energy country wide.

This is our motivation for attempting an eco-house which I hope will be an energy neutral conversion. This may not pay for itself in my lifetime but it could be a model by which the government could calculate the subsidy necessary to make every home carbon neutral.

Having just purchased a house which will benefit from a substantial extension I will record the steps I am taking and the problems I am encountering in the hope they may be valuable to others.

e chose the house because we wanted to be nearer to our grandchildren, but also wanted to live above the 75 metres contour as this could well be the sea shore in 200 to 300 years time. I wonder when estate agents will start to factor this into the price of their houses. Also the house could benefit from an extension and other improvements to the frontage and interior. This enables us to accommodate the disruption of changes to the heating etc. as part of the larger works.

The starting point

Even though I have spent the best part of a year studying the problem I find it quite difficult to know where to start. We have purchased a property which could benefit from an extension because it is quite a large house downstairs but has only 3 small bedrooms upstairs. The loft is cramped and only rises to 4 feet so a major extension would provide a first floor the size of the ground floor and could add a second floor. This could enable the roof to be turned from facing East and West to facing North and South and so being more suitable for solar generation.

Do I start by getting an architect to look at this? Is it better to research the methods of heating, like ground source or solar, first, and then call the architect to fit the building round the equipment?

I have decided (16/02/07) to research ground source heating first as this will cause the maximum disruption to the house and garden. I have found Eco-first and am going to contact them with the problem.

On the Eco-first web site I found details of the Ecobuild Exhibition at Earls Court on Feb 27th to March 1st so we decided to start by talking to people at the exhibition. We arrived quite early and managed to get in to a seminar. A representative of the Sustainable Energy Centre explained that new building standards were steadily being tightened to combat climate change but no adequate solution had yet been found to reduce carbon emissions from the 70% of houses built already and remaining after 2050.

A visiting architect asked why the standards expected in 2050 were not being applied to new builds now. No adequate explanation was given. Unfortunately the architect concerned was planning to leave the country shortly.

We chatted on the Baxi stand and they exhibited a range of heat pumps for use in ground source heating. They introduced us to Polypipe as one of the companies who specialise in underfloor pipework for ground source projects.

The Polypipe stand exhibited their new underfloor pipe panels which are only 75mm thick and suitable for use in existing buildings without needing excavation.

Another stand claimed to use Baxi pumps to produce complete solutions including solar and ground source products to suit the situation

Food for thought

The exhibition was encouraging and we started to explore what we had learned. The Polypipe panels appeared to be too thick for our existing floors as 75 mms would raise the floors above the doorsteps and reduce the ceiling heights to the detriment of the property.

My cousin's son Alan Pither has taken an interest in the project from the start and has now offered to calculate the heating requirements based on the glazed area and the other building specifications. This may be delayed until the proposed changes are clearer.

The RIBA was contacted to recommend suitable architects for the project. They proposed 3, and 2 of them made contact. One had already converted part of his house to become more carbon efficient and was very interested in the project. I provided him with a resume of the project. He asked to visit so that he could prepare a proposal.

The other worked differently. After receiving the resume he asked to visit to discuss the project for which he would charge £75 plus travel and VAT. Both are planning to come on Thursday 3rd April.

Ideal Home Exhibition

This was disappointing from an eco point of view. There were no products on display that were designed to help such a project. For example an enquiry on the Anglian Windows stand about triple glazing costs resulted in a blank stare and an assurance that they did not do them.

The futuristic house was rather better and offered leaflets on ground source heating and a range of interesting products.


We had no experience of discussing projects with architects but thought we had made our ideas quite clear in our set of notes (Appendix 1). Briefly we were trying to extend over a flat roof to add value to the house and at the same time get as near zero carbon as we could.

We had watched an episode of “Grand Designs” and been horrified by an architect who insisted on the use of materials she clearly did not understand. Both men who visited made us confident that this would not happen to us. We saw pictures of their work and were impressed with its attractiveness. They suggested ideas for our project which we discussed and made clear their scale of fees which varied from 18% of the contract price to “hopefully within 11%”. One expected the project to be over £100,000 and the other, in the report we later received, expected a total cost in the region of £200,000. We could build a new house for that!

It became clear that the methods that architects use to estimate costs might not be appropriate for our project. A cost of “between £1200 and £1600 per square metre and less than that for refurbished areas” did not give us much of an idea of value for money. They appeared to prefer larger building contractors with a good management structure and indicated that the 30% extra that this approach would cost would be worth it. How important would this extra cost be on our project?

The formal sequence of events (Appendix 2) did not appear well suited to our project unless the architect had a lot of experience in integrating the components we required.

Other architects we contacted through friends mainly thought such a project was beyond their capabilities and we appreciated their honesty. However it seemed we would pay dearly for relatively little practical experience of the methods we were planning to use. Was there another way? We needed an architect to gain planning approval and really wanted help with the appearance of the finished building but were not keen to pay fees on top of solar and ground source costs.

Initial Estimates

I decided to try to put together some of the individual costs of the features we wanted so that we could reduce the margin of error. We had noticed a local builder, Mr Philip Munt, completing the house opposite in very good time since we moved in. We phoned him up to see if he would be interested in the project.

He was very helpful and although he had not worked on such a project was very keen to try. He was aware of a ground source heating project completed in November 2006 in Waterperry. The owner was keen to share his experiences with us and said he wished he had known what he now knew. He purchased ground source heating to feed existing radiators and solar panels to provide hot water. He now realised that he could get hot water from his heat pump and the solar was not needed.

He described the process of digging trenches 1 metre deep 50 metres long in the back garden and said this had proved difficult due to the weather and the slope. However he was pleased with the supplier, Ice Energy in Eynsham, Oxfordshire. He did not have any idea of the costs of running the system yet but would let us know when his electricity bill arrived.

Mr Munt also recommended two architects who he found were good to work with so we phoned David Foale who was very interested in our project and agreed to meet us on April 13th.

Solar Century

One of the important features of our project is that the eco features should blend unobtrusively with the house for the widest possible appeal on resale. For this reason the Solar Century T21e tiles which clip together with standard tiles to make an integrated roof appear to be the best option. We met them at the Eco-Build exhibition at Earls Court. One of their partners, John Hill, Managing Director of JHS Power Solutions, agreed to meet us on April 11th.

John was very knowledgeable on all aspects of energy conservation and provided the facts and advice we needed. He had a marvellous computer program on his laptop which enabled him to calculate the likely annual power generation from our roof facing South East with a pitch of about 30 degrees. It was part of our plan to gain more loft space by increasing the pitch of the roof to perhaps 45 degrees and this appeared to make very little difference to the power we could expect of about 1641 KW per year from a Sanyo 10 panel system costing in the region of £12,297. The good news is that the government grant could pay for 50% of this cost.

He warned that a Solar Century tiled system would be 30% more expensive but their prices were currently being revised. He provided pictures of his installations and we saw some more on his website. It really seemed important to pay the extra to enable the house to blend well in the area. It was also important for us to generate more electricity than we currently needed as we knew the heat pump could be extravagant. As a result we provisionally planned for a 60 tile Solar Century system costing £10,000 net of grants and generating 2400 KW per year.

Could we afford it?

Our theory is that by the time we want to sell the house eco-houses should be selling at a premium and we would be able to recover the building costs. However we are pensioners and I am 72 in April 2007 so we would have to find someone interested in lending us the money to do this. We have a little income from a property Lanzarote but not enough to justify a mortgage based on income. Our building society which we had been with for 40 years and had just repaid was not able to help due to their need for repayment by age 75 and income based lending requirements.

I have noticed the high rates offered by the Coventry Building Society to savers for some time so we decided to open one of their over 60's saver accounts. In discussion the manager agreed to consider lending to us for the project and she was personally eager to learn how we would achieve our objectives.

In principle we had purchased a 3 bedroom house for £315,000 and hoped to turn it into a 4 bedroom eco-house worth in the region of £450,000. Having about £40,000 available, we decided to ask for £80,000 which she agreed to submit as an interest only mortgage with her recommendation to head office.

We also asked if the Coventry would consider sponsoring or promoting the project. She said there was no harm in asking, and we promised to send further details.

Gathering information

We had seen Ice Energy heat pumps at the Eco-Build Exhibition and sent them details of our project. We decided to follow this up when our neighbour had confirmed that they had been good to deal with. Having phoned at rather awkward times and requested a visit by email I eventually spoke to Adam Cusick on 13th April. He explained that they would first give me costs over the phone based on the details I had submitted and then, if I was happy, would do a site survey costing £500 which would be refunded out of the total cost if I went ahead. This seemed reasonable, with the other safeguards he mentioned, as they must be inundated with time wasters.

I do like a company that starts with the costs instead of concealing them until the end of the negotiations! Factors like the usage of hot water and the size of my garden were taken into account and we arrived at a cost of £7058 for a 7kw system with a 400 litre hot water tank. A grant is available of £1500 making the net cost £5558. To this should be added the cost of digging the trench 1 metre wide and 1 metre deep for 50 metres. We estimated this at £2000 but I rather look forward to hiring a digger and doing this myself!

A heat pump uses electrical energy to produce heat rather like the back of a refrigerator gets hot when the fridge gets cooler. Adam said they expect to multiply the heat value of the electricity 4 times. He was expecting we would use the existing radiators to do this but I had heard that even better results could be obtained by using underfloor heating pipes and running the system at a lower temperature. The installation would cost more so there is a trade off.

The time scale for Ice Energy was 2 weeks to get a survey, 2 weeks for the ground works and 8 to 10 weeks for the heat pump making a total of about 12 weeks from the go ahead.

A new architect

Our meeting with David Foale proved to be a landmark. He had recently become a member of the Eco Building Association and came armed with their magazine. He saw this as the way his work should develop and proved to be most knowledgable and willing to share his knowledge. He was keen to work flexibly with us to save costs.

He liked to manage projects rather than just preparing designs, but appreciated that I had spent considerable time researching the components of the project so was happy to do what was needed and leave to me what I could do. In particular he felt a competent builder like Philip Munt would be able to undertake a project like this by discussing minor issues with me and with minimal involvement from him.

It was clear that we would rely very much on him for the design work and planning application and after that a bill of materials would be prepared so that we could all see what was being achieved for the money. This would enable builders to tender and a good result to be achieved. He suggested Cherwell would be asked to appoint a building officer for a fee of £350 who would attend and approve each stage as it was completed.

We covered a lot of ground discussing double and triple glazing, the planning difficulties of raising roof levels, the problems of ground source heating distribution, timber cladding, the valuation of properties at the design stage, relationships with estate agents, the disadvantages of Bradstone block buildings, stresses in lintels and many other matters. All this time was given freely and we had entered a new relationship.

Costs appeared likely in thousands rather than 10's of thousands and the project appeared viable again!


We were impressed with the potential of the roof sealing systems which spray foam onto the underside of the tiles for insulation and cleanliness. Having tried to insulate lofts in the past you have a dirty job and difficult decisions to make. If you insulate the ceiling deeply the loft becomes unusable for storage and remains dirty. The tank and pipes are in danger of freezing. Insulating the pitch of the roof is much more satisfactory but very time consuming as all the insulation needs to be supported on battens or plasterboard. Plasterboard is the better choice as it keeps out the dust and improves the appearance.

We found 2 roof sealing contractors at the Ideal Home Exhibition, Warmroof and Sprayseal. The first is a franchise and the local agent came to assess our project on the evening of April 13th. Mr Bob Bullen was a friendly man with a great deal of experience as a roofer. He preferred to quote for the whole of the tiling and sealing together but it was important for comparison purposes to have his “new roof” quote for the sealing alone. This was £7300 for 130 sq metres of roof requiring no remedial work. This seemed rather a lot and we resolved to compare it with more conventional methods. He promised that 100 mms of coating would achieve 0.01w/sqm/degree.

The leaflet prepared by Sprayseal, the family firm, promised 0.2w/sqm/degree with 95mm of coating which appeared a little more likely.

Underfloor heating

The discussion with Bob Bullen explored the problems of wall and floor insulation. Although he was not offering these products he recommended extruded polystyrene as the most efficient insulation. In walls it can only be used in new builds (or new extensions) and it can be used under floors if protected by a concrete screed. He has used it effectively in his own property.

This leaves me thinking that the walls in the extension could be thicker than the floor below to increase insulation and also give an attractive overhang to the front facade.

While looking at the walls to gain an idea of the current cavity fill, if any, Bob commented on the Bradstone which is currently out of favour with planners who prefer real stone facades to reconstituted stone. We looked at our house through new eyes and understood why it would not suit everyone. Having said that we were very happy with the condition and appearance of the walls which have weathered quite attractively.

Living in the house

We purchased a house almost obscured from the road by uninteresting bushes, with the exception of one glorious forsythia. The small rear garden was narrowed by an overgrown fir hedge. We vowed to clear the front garden as a first priority but of course matters inside prevailed.

Outside we removed some of the bushes in the front while leaving the forsythia to enjoy its last year of bloom!

We cut down the fir hedge and, to avoid pollution, had it shredded to make wood chips to lighten the clay soil. You can see the part used pile of chips behind later prunings. We ground the stumps of the hedge and of some other trees felled by our predecessors to make way for the ground source trench if needed (or for cultivation). The chipper and the stump grinding work cost us £350.

Our grandson Olly worked hard to smash up a concrete coal bunker and we used the rubble to extend the driveway.

The steepness of the drive was becoming apparent and as a result we started to plan for the house to stand above a lowered driveway making it more imposing.

Blending the solar tiles

The Solar Century datasheet lists 7 tiles which are compatible with their C21e tile. As our objective was to achieve the nearest colour and texture match we looked on their websites and provisionally chose Marley (Eternit) Modern Anthracite as a very black and slightly shiny tile very similar to a slate.

Another architect

Mike Gregory heard of our project and contacted us today. He was recommended by an architect who said this type of work was not his forte. Mike too claimed to have no experience of this kind of project. We are coming to the view that we need to separate the visual and space planning part of the project from the eco-equipment part so that we can divide responsibilities better. We have agreed to see him on Wednesday 25th April.

Ground Source Heating

I have been wrestling with the problem that a heat pump works most efficiently if it can be run at lower output temperature. This is why new builds have massive underfloor pipework installations. In an existing house it is not usually practical to rip up the ground floor to a depth of at least 75mm to install such pipework so the existing radiators are usually used.

I have come up with the idea that pipes in the walls could be a useful alternative with several advantages.

I must discover any existing installations and their problems.

Hot water cylinder

Although our heating and water system will probably have to change I though I would experiment with the existing cylinder which has the old fashioned red felt jacket for insulation. How easy is it to improve the heat retention by injecting foam beneath the jacket?

My first attempt was poor as I was quite concerned I would be overwhelmed by the foam, which expands to 30 time its volume! My short squirts beneath the tank jacket sounded spectacular but only left a small patch of foam stuck to the tank!

The foam set in the tubes of the applicator and took 20 minutes to clean out! At my next attempt I determined to use all the remaining product to avoid the cleaning job at the end.

Yes, that went better! The foam stuck well to the wettened tank and sealed the jacket better, particularly at the top where the insulation is most needed.

Michael Gregory – Architect and Illustrator

Michael had received our proposal from Alan Clarke but was not able to see us before. It was a most valuable meeting as he had studied our proposal and identified well with our objectives. He was most generous with his advice on all manner of matters.

As evidence of his work he produced a file of drawings which he had used to gain planning permission together with the full drawings for the builder. These were beautifully hand prepared and quite a work of art in themselves.

It was difficult to gain a clear idea of the cost of his work. He was prepared to undertake the whole job for a percentage, but he did not suggest what percentage. His draft planning application would cost in the region of £500 as long as there were not too many changes. This appeared to take one half day but that was probably the drawing after the principles had been agreed.

He said the work on the large sample project he did had cost £4500 which appears very reasonable. He said he preferred to charge for the time he spends per half day, but did not say what a half day would cost.

I am inclined to think that his advice would be very valuable and will try to retain his services as a second opinion. In order to do this I will send him a cheque for £150 for studying the project attending today and ask if he would be willing to attend some meetings for a similar fee.

It also occurs to me that should these notes be published he would be an excellent illustrator.

I have talked to one or two people about this idea and they seem to think it has merit if David Foale is in agreement.

Which first on 27th April?

I am conscious that we are going on holiday on May 9th so have only 2 weeks to do what is necessary before a 3 week break. With that in mind I phoned Adam Cusick of Ice Energy to see if a survey costing £500 was the next step to take. He warned me that by ordering a survey I was committing myself to the purchase of a heat pump with a total cost of £5500 after grants. He was required to make sure that I had planned and costed my ground works and understood my plumbing needs before he accepted a cheque for £500.

He said there was no hurry to fit in with my building plans and the surveyor would be more useful after we had a clear idea of the building structure. I respected him for this caution.

At least David Foale has agreed to have a key and start the drawings while we are away so there can be some progress.

How good is my insulation?

I do want to apply the most effective insulation to my house as this will save energy and enable me to run my ground source heating at a lower temperature. At the moment I don't know what is the best cavity wall insulation and I don't want to rely on the salesman to tell me! I probably want to know the effectiveness of my walls and floor now and to be able to measure how much better they are after they are insulated.

How could I do this? If I could measure the surface temperature of the outside walls, the inside walls and the objects in the room I should be able to get a good idea of how much that wall was cooling the room. I started looking on the internet for a surface thermometer and read an article saying these had been replaced by Infra Red (IR) thermometers which could very quickly measure the temperature of a surface. Then looking on Ebay I found one for £10.56 including postage. Having a little birthday money I invested.

Energy usage

I have just received my first electricity bill at this house. It was much too high, based on an estimated reading, so I decided to take a customer reading. The meter shows a day and a night reading and I was surprised to find that we had used 400 units in the night and 420 units by day. Was there a leakage or some equipment I had been leaving on.

My meter flashes each time it uses a watt hour of electricity ( one thousand flashes to make a unit). As it was evening now was a good time to calculate the night time usage. I counted the seconds between the flashes and found about twenty. This worked out at 180 watts of load so I started turning off some things like computers, TV, VCR, freezer (in case it cut in and upset my measurements) and PIR lighting. I left one 25 watt bulb on so that I would not have to wait too long for the flash!

This time it was 60 seconds between the flashes so a 60 watt load of which 25 was my lamp so only 35 for the microwave and cooker which we do not turn off because we would have to reset the clock.

That sounded about right but really encouraged me to turn off those appliances at the wall each night and during the day when not in use. Oops, did I remember to turn the freezer back on!

Progress on the driveway?

A passing Irishman noticed the part completed driveway as he passed and offered to tidy it up for me. He plans to use the grade 1 binding gravel they use on the motorways to overlay my rubble and crush it down with a heavy roller. He offered to do this for £200 and it may be worth the money as I was expecting to pay £100 for the materials and use the car to crush down! I asked for his card and he did not have one. I asked if he was local and he said yes and mentioned a village 4 miles away at Arncott. I may be a fool, but it will have to be renewed when the builders have finished anyway.

Update on Solar Costs 27/04/07

I made a call to John Hill to get an update on the prices of solar tiles which he had said could be coming down. He informed me that a new arrangement for grants was expected by the end of May which was expected to limit grants to £2000 per KW peak with a maximum of £5000. Planning will have to be obtained in advance and the grant must be used in 6 months.

He said the current scheme was due to end in December but at the current take up the funds would last 2 years.

He promised to send the latest details on the Solar Century tiles and said that the Anthracite roofing tiles were a very good match for the solar tiles. He said the glass tiles keep clear with the rain and do not need any cleaning to remain effective.

Ideas from ITV “Grand Designs”

We now watch “Grand Designs” whenever convenient even though the motives and priorities of many of the clients are quite different from ours. Tonight we noticed that a builder was using quite a thin (20mm?) board for insulation under the tiles, which was expensive, but the equivalent of 100mm of sheepswool. The board was called an isocyanate board and I determined to research further. Isocyanates were an ingredient of the foam I had used to try to insulate the hot water tank and I suspect this is the kind of material used on modern hot water tanks too.

Second meeting with the architect 09/05/07

This meeting was to get the project moving while we are away on holiday. First David Boale took us to see some of the work he had been involved in locally. There were interesting ideas completed in a cost effective way. Some properties which were quite ugly had been improved and others had been extended in a sympathetic and pleasing way. Materials had been appropriately natural stone, timber and rendered brick.

On returning to his office we were pleased to find he had drafted some floor plans based on our estate agent copies. They were initially quite different from what we had in mind, but as he explained, they appeared to achieve our objectives very well. As a family man himself he could envisage the requirements of a modern family buyer much better than we could.

He had moved the staircase to make better use of the view from the rear of the house by siting 3 bedrooms there while the front of the house was extended within the existing roof line with 3 dormer windows. This dramatically improved the appearance at the front but did not provide as much additional space as my draft. As a result we agreed to try to raise the roof line, even though this might cause planning difficulties, and provide enough headroom for a loft room later. This might be acceptable as the next door roof line is already 1.5 metres higher than ours. A porch was also discussed.

We agreed to go ahead on this broad basis to draw up some plans which might be submitted for a planning opinion.

David asked for more details of the solar I was interested in and I agreed to send him the data.


Some decorating and minor repairs are needed to make the house habitable for this year. We have done the 3rd bedroom as an office and the guest room and have started the small cloakroom and the kitchen. It's some time since I have done any decorating and I find I am a bit out of practice. I'm making the same mistakes I have made before. For example I use Fine Surface Polyfiller far too much under the mistaken impression that it will give a finer result. In fact iit is a very specialised product for smoothing very fine imperfections in the surface. The problem with using it more widely is that it is very hard and difficult to sandpaper.

I have just started using a sanding block again and have been getting some much better results with standard, mix yourself, fillers. They are softer and sand down to leave a very true surface which paints without any imperfections.

I often make the mistake of buying paint bargains too. When you put time and effort into preparation and application it is surely worth paying a bit more for a good quality paint that goes on well. I am trying the Dulux Flex range as it claims to cover fine cracks even when the ceiling moves a little. I will let you know if it works.

Insulation – do we have enough?

General advice suggests that money spent on insulation is generally better than money spent on technology to achieve a zero carbon house. The problem is that the effectiveness of the insulation of a wall or a roof depend on estimates based on the materials used and the way they are put together. I want to measure the effectiveness of a wall in some way. The materials are measured in watts per degree per cubit metre of material (U value) but the complex structures in roof, floor or walls are difficult to estimate. I thought if I could measure the surface temperature of the inside and the outside of a wall there may be some calculation that could be made to indicate its effectiveness as an insulator.

With this in mind I searched the internet for some instrument that would measure the temperature on a surface, fearing it would then be too expensive. I was amazed to learn that surface temperatures are now measured using an infrared laser device and that they cost about £7 on Ebay with £6 postage from Hongkong!

My device arrived last week and a good opportunity to try it out came when we had a cold windy night outside in May and used the heating. I made the following readings:-


Reading C





Internal Glass Door


Catching radiated heat from radiator?



Cooled from Underfloor

Internal Wall


Probable air temperature

External Wall


Cooled from outside

Window Inside


Ordinary double glazing




Damp and windy conditions



Away from house


Water surface


Interesting! Evaporation effect?

Related Conclusions and Questions

  1. The surface thermometer is not accurate enough for any but broad conclusions

  2. Bear in mind the walls are cavities not filled and the floor is parquet carpeted.

  3. An 11 degree difference between inside and outside is the minimum for any conclusions.

  4. A ceiling measurement should be taken to complete the picture for each room

  5. The floor (carpet) and the external walls cool the room to an equal extent per sq metre.

  6. The inside window temperature of 12.8 differs from the room by 3.2 degrees indicating over 3 times the heat losses compared with the walls per square metre.

  7. If the windows are conducting heat at 3 times the rate of the walls this should make the outside of the windows much warmer than the walls but they are only 0.8 degrees warmer.

  8. Does the amazingly low temperature of the water surface make sense? Can it be repeated? What does it mean for wet roofs and walls?

  9. The method could be used to identify gaps in the insulation in the walls and floor but will not indicate U values at all accurately.

Insulation Materials

I don’t know much about the relative merits of insulation materials. After my experience with the Warmroof salesman and being bewildered by the options I did an internet search and came up with the material Polyisocyanurate. A visit to the local builders merchant and I had a product booklet to study but he would not give me any idea of price until he knew what quantities and thickness I needed.

Flat Roof

Half the flat roof has looked cracked since we moved in but now we have had some heavy rain it is starting to leak in two places. I had bought some sticky black stuff expecting an emergency like this so in a break in the rain I tried to seal the worst places. A had some success but as I walked on the roof the water oozed up from below so it was clear there would soon be more leaks. Rather than do work on it I planned a tarpaulin to cover it for the time being. This gave me another reason for having a chat with our preferred builder.

Keeping the Builder up to date

I feel in general that if you consider others they will consider you. This rather runs across the conventional approach of designing a building and then putting the work out to tender. I wanted to find out a convenient slot in our favoured builders programme and then aim for it. He popped in and we talked a bit about the relative cost of pitched dormer windows which concerned me.

He explained that he had had a large job deferred until next year so it would be advantageous for him if we could start to work in August or soon after. We agreed to aim for this.

We mentioned our problem with the flat roof and he agreed to pop a tarpaulin over this next week.

Our Holiday

Then we left for 3 weeks holiday in Lanzarote. You may condemn us for our use of air travel at a time like this. Yes I do believe that air travel will need to be rationed as part of a scheme to reduce carbon emissions by 90%. However I don’t believe that my failure to fly would accelerate that legislation. I would like to be able to lead on every front but this is too much for any private individual of modest means. My priorities include visiting my grandchildren in Lanzarote but I am changing my habits to visit for longer at a time and less often.

If I can show that an ordinary house can be made carbon neutral and more attractive then I will have contributed significantly to the future for my grandchildren.

Back Home again 09/06/07

Weather has been good so we have given the garden a blitz. We removed the overgrown forsythia which divided the front garden in two, removed the gate behind it, and cut back the neighbour’s overhanging beach branches with his permission. I have a little bag of logs to give him! Now we can get the feel of the front of the house.

I continued my study of insulation and conductivity. I learned at school that most materials like metals that conduct electricity also conduct heat well. I thus assumed that ceramics and concrete that did not conduct electricity would be similar in not conducting heat. I needed some better information and found it on the website of a wood stove manufacturer.

Common K and R Values Chart


K value

R Value

| inches-K value .84

| inches-R value of 1

per inch

Micore 300*





Wonderboard (cement board)*





Common Brick





Cement Mortar





Ceramic Tile










Air Space (ventilated)





sand and gravel





Drywall (gypsum)





Rockwool or Fiberglass Batts*





This gives me a lot of food for thought in planning under floor heating. Ideally we need highly conductive materials like marble and ceramics on top of the heating pipes as thin as possible and the best insulation possible below the pipes. Carpeting and wooden floors will make the heating system less efficient and energy will be wasted.

The first Plans

Meeting with the Architect 14/06/07

David Foale presented his plans for the project. With his approval I invited Michael Gregory to the meeting and it worked very well. One plan was presented along lines we had previously discussed which involved enlarging the present roof forward and placing three dormer windows at the front. The plans below were presented as providing better usable space upstairs without raising the roof line. Both architects claimed this was important if the plans were to be approved easily and quickly. They also replicated the 33 degree pitch of the existing roofs in the extension gable which the planning officer would prefer.

These were plans in pencil on A4 paper and it can be seen where some alternatives were discussed.

I was surprised initially by the total change in appearance David had achieved. I was expecting something much more traditional and the low pitch and triangular appearance of the front took a little getting used to. However the low pitch flat extension roof to the South West would present the solar tiles to the sun very well. If needed there would be an area of South Easterly roof as well. A porch had been added which echoed the roof pitch and could enable a part-carport in front of the garage. If our neighbour approved this style of roof could be repeated over her garage to good effect.

I awoke with concerns 15/06/07

I was concerned that the triangular windows and modern front of the house might not be suitable in an Oxfordshire village which treasured its traditional styles. Also how would the neighbours react to living beside such a dramatic building? Would anyone looking for a village house consider such an unusual one?

I doubted whether the large en-suite would be valued more than an extra bathroom as 3 bathroom houses are becoming quite popular. However the galleried hall and light well limits access to the en-suite area by others in the house so this could not easily be subdivided.

I started to take opinions over the weekend. My son-in-law liked the design but shared my concerns. My daughter disagreed and loved the design saying she would love a luxury bathroom. My daughter in Lanzarote said the design was not too modern, unless executed in stainless steel!

Kevin and Sue next door said they liked it very much, so it looks as though I was wrong to worry.

Even so I wrote to the architect to delay submitting the plans for planning until the other neighbour had been consulted on her return next week.

This gives me a week to take some more opinions.

Viewpoints 20/06/07

Our daughter suggested a similar house had been built in Long Crendon, an attractive nearby village. We visited and took some photos you can see below.

It was evident that a traditional village with much stone and thatch could also blend with modern features and a very modern house.

However we needed to know what made our village so attractive and the styles that were incorporated. We are on the edge of the village so you would not be expecting a cute village green house anyway. We took the photos below.

Starting at the Millennium Hall, the style chosen by the parish, the church is the focus at the bottom of the village. Close by are two small closes and opposite them the side of the hotel looks across a small green. The front of the hotel is traditional but beside it is a very white block bungalow.

As the hill rises some of the most attractive village features appear including the iconic almshouses.

Leaving the village to the North the Brill Road continues with a mixture of quaint thatch, substantial period properties and farmhouses interspersed with basic housing.

I think I am convinced that a good looking building can be an asset and does not have to be tied to traditional styles.

Markets and Mortgages

I had phoned Lloyds TSB during the week to find out what kind of loan would be suitable. I have been a customer for 30 years. I talked about £100,000 as we now seem to be doing more rather than less and need to funds to get it right. They said I should drop in to any local branch to talk it over. I called in to the Headington Branch and was seen almost immediately. They were helpful and we discussed the options. The first would be a mortgage from Cheltenham and Gloucester but they have a need for repayment by the age of 75. The second would be business loan. The third could be equity release which might be the best in view of my age.

I suggested that Lloyds might be planning a special eco-loan product for the future as many people would wish to take this route in the years to come. He said he would not have the contacts to discuss that option.

He said C&G would phone me.

While in Headington I popped in to see Jonathan Seabert in Chancellors to start to talk valuations. He had worked hard to sell us the property and his manager Will had been innovative in keeping buyer and seller together over months of difficulty.

Jonathan was as friendly as ever. He called the team over to meet me and said I was quite a celebrity with them. He pulled the plans of the property up on his screen and I explained briefly the changes we had in mind. I should have brought the sketches but he went through with me recent sales in the village and offered a guide of £365,000 to £375,000.

This was disappointing as it was only £50,000 to £60,000 above the price we paid, but my researches with Prime Location and Rightmove websites suggested a well presented 4 bedroom 2 bathroom house in the villages East of Oxford could fetch a great deal more than that.

They were interested in our plans for an eco-house and said they might be able to feature it in their magazine. This could be very attractive.

Cheltenham and Gloucester 20/06/07

I had been home a couple of hours when Cheltenham and Gloucester phoned to offer £100,000 on what appear to me to be very favourable rates. The interest only mortgage would run until I was 75 at 0.49% over base rate but then could be renewed for a further 5 years to enable me to sell the property. I could repay the principle as I wished during that period without penalty. I agreed to go ahead and asked for the papers to be sent to me.

Comparing this with the offer our son-in-law got recently it is 0.33% worse rate but this is not surprising in view of age and lack of income. We think we might give his mortgage broker a try to be safe.


A rather chilly night reminded me to study the problems of ventilation. Betty likes fresh air but does not like to be cold. This tends to add to costs by heating rooms with open windows! My friend Rob Williams made me aware of a company that gathered solar heat by drawing air from under the tiles and redistributes it round the house.

David Foale said he planned to recover heat from the utility room, bathroom kitchen and cloakroom extractor fans so we will see what circulation of air that provides.

Revised Drawings 21/06/07

David emailed his revised drawings today.

The link with next door is now clearer for our neighbour to consider.

Bedroom 3 is now larger than the en-suite and more useful.

I must work out the implications for solar generation of the flattened roof to 28 degrees.

Ground Floor

The rear extension needs some discussion as it has not provided the comfortable breakfast area we had hoped but contains sink, cooker and lots of cupboards.

The loo and utility room have swallowed half the old kitchen. Otherwise, as before, we are very pleased.

Solar Calculations 24/06/07

I tried to get new calculations of the power we might generate from the new roof design by emailing JHS Solar. While they sent some useful data on the fixing of Kyocera solar panels they did not respond directly to my question. They are very busy people so it was time to try some calculations of my own.

I found the US Government website which enables you to input the physical details and obtain an estimate of the power you should generate in the year. By putting PVWATTS into Google you can find the page which will enable you to do your calculation.

I haven’t yet decided on the size of my solar array but just wanted to know how much efficiency I would lose or gain by changing the roof line.

Old plans

With a 4kW DC array in London facing South East on a 40 degree roof we would expect to generate 2963 kwh electricity in the year.

New plans

With the same array facing South West on a 28 degree roof we would expect to generate 3100 kwh electricity per year.

The ideal roof

Should face South at a 51 degree pitch and this would generate 3163 kwh in the year.

This means the new roof is better than the old and only 2% less efficient than the ideal.

Out of curiosity I prepared the following table from US Government Data

Kwh per year

28 pitch

40 pitch

51 pitch













Interesting that 51 degrees is not the ideal pitch for London, and that the difference between the pitches and directions of the roofs is less that I expected.

NPower Enquiry

It’s time to see what arrangements are available to buy back the electricity we generate. I wrote to NPower as I had heard that they would buy back at the same rate as they charged us. This seemed rather too good to be true. I received a very helpful reply.

Dear Mr Malcolm Crocker

Npower does run a Microgeneration Scheme where we buy back exported
electricity for systems of 6kWh or less and are Residential customers. To
take advantage of this scheme you do need to be an Npower Juice customer for
your import electricity, if you are not already and would like more details
about npowers green tariff 'Juice' please call 0800 316 2610.

Juice is generated from a number of renewable energy sources, primarily at
North Hoyle Offshore Wind Farm. As a Juice customer, npower matches every
unit of normal electricity that you use and feeds the same amount, generated
from renewable sources, into the electricity network

Npowers buy back rate for your area would be 8.44p per kWh exported
electricity. Currently we are not installing an export meter. We will ask
for meter readings twice a year (April 07 and October 07), this will be from
your generation meter unless you already have an export meter installed. We
have to estimate your export from your generation meter reading, Industry
Studies state that 50% of what you generate you consume and 50% you export,
this is the formula we base our calculations on. Payment is sent as a cheque
to you.  We do obviously keep all customer details on our database and it is
noted whether you do or do not have an export meter.  If the time arises
when we are in a position to install the export meter we can then put
customers on a waiting list.  We will write to all of customers to inform
them of this, if and when the time arises.

We would ask that you appoint us as your ROC Agent. This basically means
that we will be able to register you with OFGEM and collect your ROC's
allocated annually on your behalf cutting lots of paperwork out for our
customers. Basically you will just receive your cheque for payment of your
ROC's. Our current Buy Out price (set by OFGEM) is £34.30 per ROC.

I attach our Microgeneration Information pack.

If you have any further questions please do not hesitate to contact me.

Many thanks

Sue Warman
Microgeneration Scheme Handler
npower Residential
Oak House, Worcester
  01905 340646 (Int. 2646)

The information pack attached to this was slightly different. It suggested we must have an Export meter. From my point of view it is very important to know exactly how much energy we use and how much we export so I resolved to get an export meter.

How many solar panels of what size?

John Hill of JWH Solar most recently talked of Kyocera panels so I had better find out their rating and size. The datasheets show a 200watt panel with dimensions 1425 x 990 mm and a depth of 36mm including the junction box. They claim a conversion efficiency of 16% which may be why they are recommended. Kyocera also claim the world record for efficiency of 18.5% but this cell is not yet in production.

I phoned John regarding cost and he said 10 of the panels would cost £9850 plus the fixing kit as long as the scaffolding was available from the roofer. These would produce 2KW peak power and about 1800 kwh during the year. Less the grant this would come to £7350.

I thought perhaps 14 panels would be better bearing in mind the power the ground source heating would use, and he quoted £13301 plus the fixing kit giving 2520 kwh in the year.

This power would be purchased by NPower at 8.44 pence per kwh earning £212.69 which on an investment of £11,000 would be about 2% return.

The real return is expected to be on selling the house at a premium.

Our Neighbour next door

Professor Frances Ashcroft MRS or Fran as she likes to be called is one of the top scientists in the country and has won awards for her team’s work in understanding diabetes. She has been away lecturing and on holiday for 3 weeks and agreed to come to discuss the plans last night. Her viewpoint is of vital importance to us. We want to remain in a good neighbourly relationship and we would not wish to divert her from her valuable work.

She had expressed concern about her garage flat roof and this is why we asked our architect to sketch a pitched roof in harmony with our porch.

She expressed doubts about the windows right up against the roof and also felt that she was disadvantaged by the grander appearance we had achieved. This diminished her house.

She then discussed rebuilding the garage as a guest room with a first floor extension overhead which would enable her to entertain without stress, and could compensate for the loss of view from her bathroom.

She agreed to call David Foale to see whether these ideas could be incorporated in a joint plan though she did not want us to delay our planning application, particularly in view of our leaking flat roof.

Discussing this afterwards with Betty we realised that we could not both extend by building on top of the party wall. If we did the houses would become semi-detached with a consequent loss in value. However if Fran were to build 2 feet back from the party wall the houses would become detached with a gain in value.

Interesting scope for discussion.

Meeting together 16/07/07

Our next door neighbour, Fran, and David, our architect agreed to meet together with us to work out the best solution for all of us. David had circulated a plan which separated our properties completely with a 60mm gap but advised against this on grounds of cost and appearance.

Fran offered an alternative in which she would set back her 1st floor extension to leave an air gap at first floor. We would still be joined at the garage but this would count as link detached as long as we did not later develop our garage into a room. This we were very pleased about.

We discussed a stone drainpipe between the two houses and the possibility of a Velux window to enable the valley gutter to be cleared if it became choked.

Fran then worked with David to discuss the options for her extension. She has a very quick mind and drew illustrations while she was talking at an amazing rate.

New Front Drawings

David forwarded these drawings with a note that he might flatten the pitch of our roof to match Fran’s extension and give us a little more headroom as a result.

We responded approvingly and asked whether there would be a matching stone downpipe on the left of Marchwood. We want to gather rainwater but are concerned that 75% of the water will be gathered at the front of the house. Will we store it at the front underground or lead it round to the back? Recent very heavy downpours can be expected to get worse in future years and the size of rainwater pipes and drains may have to increase.

Discussions Continue

Discussions between Fran and David have continued and on 6th August David said he was on hold waiting for more of Fran's ideas. We spoke to Fran and she thought all was going ahead. I spoke again to David and it appeared to be, however it is now 13th and there is no more news.

Energy saving building choices

It is fine to achieve a zero carbon result but it is desirable to achieve this with the minimum carbon footprint. At this stage we have chosen:-

1. To use the existing hardwood kitchen and remodel it rather than cutting down more hardwood forest.

2. To attempt a gravel drive rather than cement or concrete

3. To use recycled blocks for the additional walls rather than new concrete blocks

Oxfordshire Climate Exchange 17/08/07

My searches for those active in eco-renovation led to Oxford University Centre for the Environment, Environmental Change Institute, and their initiative for Oxfordshire called ClimateX. Here was an opportunity to help others, compare notes and get advice in the best possible way. Jo Hamilton, the Co-ordinator, responded to my email with encouragement so I offered to work one day per week with them on a voluntary basis.

They had planned an Open Eco-house Weekend in November in partnership with Climate Outreach and Information Network (COIN) and I was able to help with the preparation of materials though I was not available to help on the day. It is great to be working with those better informed and more enthusiastic than I am from the University and I even was allowed in to some of the lectures which put the problems in perspective.

I joined the email newsletter and found more events all over the county where eco-villages and other community efforts are starting. COIN have started a web site especially to help eco-renovation called . The main web sites are and

Our plans have at long last gone in! 25/08/07

David came round last night to show us the final version, He has been great at keeping up with all our questions. Our last thought was that perhaps a frontage in real stone might be a good option as most of the frontage will have to be rebuilt anyway. He said Bradstone was cheaper to lay and cheaper to buy but if we wanted to change to real stone it would only need a small amendment at a later stage.

He agreed that it now looked unlikely that we could make a start before Christmas so it would be better to wait until well into the New Year. This would solve some problems for us as we wanted to house our daughters family from Lanzarote over Christmas.

We talked a little about costs and he thought the building and electrical work would cost between £70,000 and £85,000. Double glazed units for a house slightly larger than ours had recently cost £13,000. With solar at £13,000, heat pump and plumbing at £10,000, bathrooms £7000, kitchen £3000, garden £8,000 and architect £7000 we would total £131,000 at least. I need to do some more work on this.

David also said that planning required 30% of our lighting to be energy saving. Strange if we are generating our own electricity, but we intended to make as much as possible energy saving anyway.

Lighting Research 27/08/07

We have spent most of the long weekend putting up pictures, installing lighting, tidying the garden and preparing to live in the house as is for a further 5 months including Christmas. We purchased some circular fluorescent fittings, 40w for £45 each, so have put the last of these up in the kitchen. They are an improvement in appearance on the 3 fluorescent strip lights that were there, and give similar brightness, but are not wonderful.

We chose uplighters for the dining room so that the bulbs would not show and we could use the 20w mini fluorescents which yield about 100w each. The uplighter fittings were £5.95 in Homebase and the mini fluorescent bulbs were £1.35 in Tesco.

Once again I have been searching for bright LED fittings for areas where fluorescents look ugly. I do like some sparkle, which LED's can provide, but I can't find fittings I like. I will have to go and look at some components to see if I can do better!

We have tried a few different shades in the hall as we want to use eco-lighting but want a well lit hall. The ordinary cylindrical shades left a small patch on the floor and another light patch on the ceiling but did not light the hall adequately. We tried the cone type which throw the light on the ceiling. This hid the bulb well but resulted in a dim hallway. The best we found was a Tiffany style shade from Homebase at £12. It lit the hall well because of its translucency but also obscured the bulb shape. We have used that for the landing too.

Planning department visit 14/09/07

A member of the planning department arrived today and Betty showed him round. He expressed surprise that he had 6 pages of drawings when he usually only received one page. After a brief discussion he said he did not think there would be a problem but the architect would have the final say. We would get the answer late in October making 8 weeks in all.

Making changes economically 29/09/07

If the changes we make are so costly to make in energy terms then they cannot be a prototype solution for the world's problems. Cement production generates one 6th of all the CO2 emissions globally so we want to use as little as possible of it. Lime based products are better but not much better. More work is needed on this. Ideally an oil based product which replaced cement would provide an alternative, non-emitting use for oil and provide compensating revenue for the oil companies. Of course it would be more expensive but how much is the planet worth?

Our driveway is a case in point so while waiting for the planning I decided to excavate carefully round the oak tree to see whether we could lower the drive to set off the house better. This entails removing asphalt so I phoned the local authority to see if this could be recycled. No! They said but the contractor who removed it might be aware of the way it could be done. A phone call to a few contractors drew a blank. A call to Cotswold Waste and Recycling Ltd 01865 516851 was successful and I agreed to put on asphalt in the skip to facilitate this.

I cut into the asphalt at one corner and measured its thickness as about 3 inches. I measured the area I had to remove at the base of the tree at 3 yards by 4 yards and so calculated that I would need approximately a 3 cubic yard skip.

The day before the skip arrived and Irishman called to offer his services. He was working just up the road at Mrs Hendry's and could bring down the 'grabber' and have the job done in no time. I explained what I was going to do including barrowing the surplus soil round the back for landscaping. He said he had a gang of lads who would be happy to do that. He was in the Yellow Pages and a Limited Company so quite reliable. I told him about my previous experience and pointed to the shifting pea shingle entrance. He said that guy was a crook, which made me feel much better! I told him my wife would kill me if I made another mistake like that. He checked a few more details and offered to do the job for £1200, which he then changed to £1250 before I could say yes or no! I said I would consider his quote after the builders had done their work in the Spring. I hope he doesn't send the 'grabber' round anyway!

The skip arrived promptly at 8 am as arranged and was placed in the exact spot most convenient for me. Lifting asphalt is easier than you think. Once you have made a small hole in the surface you put a spike as a lever under and gently prise the whole slab up. If you are lucky it separates into biscuit like slabs of up to 20kg each to lift into the skip. I was surprised that the asphalt generally much thinner than the corner I had tested. It was about 4 cms thick at one end but tapered to less that 2 cms or 1 inch at the other. At this end it was already breaking up and lifted in smaller pieces.

By lunch time I had lifted the area I needed, only about one third filled the skip, and was considering how much further to go. My neighbour who farms in the area came across at this point to see what the crashing was all about. He said that an oak tree roots go almost straight down and there would be no problem lowering the driveway. He said you can plough right up to an oak but an ash spreads its roots outward much further. Then Richard Hayes, the local landscape gardener arrived and confirmed this.

Underneath there was a sandy gravelly base which should be OK until the building work started so I decided to take most of the asphalt up. Here goes!

30/09/07 – A marvellous weekend! I achieved far more than I expected and managed to take up all the asphalt except the bit the skip is sitting on.

Planning Problems 11/10/07

After a bit of a lull we were surprised to receive a copy of a letter our neighbour Fran had sent to the planning department. After agreeing verbally in several meetings and working on complimentary development of her property she had expressed regret that we did not wait for her plans to go in at the same time. She then made several complaints about the details saying they would restrict her light and view from her bathroom. This made our architect look foolish as he had said to the planners that both neighbours were in agreement.

These complaints did not appear to carry any weight in planning terms so we were even more surprised to learn that the planner was asking us to withdraw out application and resubmit it later to be considered together with Fran's, with a resultant 6 weeks delay. He even said he could not recommend the application in its present form.

Our architect was happy to do this but we felt it was unsatisfactory as the planners have a statutory obligation to decide on the application in 8 weeks and we did not want to agree to a delay. The roof, which had been covered with tarpaulins in May was still leaking occasionally and we felt it was unwise to agree to further delays. He has conveyed our wishes so we will see what happens!

The application for Stonecroft is submitted 31/10/07

At last David Foale has submitted the application from Fran next door for her complementary extension. I should be able to see it on line but have been assured that it is as was agreed. Hopefully the planners can see how wel it fits with ours and there will be no further delays.

Front Garden 05/11/07

I have had 'flu for a couple of weeks so have not been continuing the work on the front garden. Last week Betty's brother Jim and his wife Carol arrived from Canada. As well as a few days out together he helped me to start the project by removing the driveway base which had been under the asphalt drive. I was on antibiotics so did not have much energy so Jim did most of the work. We piled it up ready to relay after the drive was lowered.

The next stage was to lower the drive so that it swept evenly down to the road. In places we removed two spits of soil which appeared to be good topsoil. We found a few roots from trees and bushes but none of the large roots we feared. By the 10th November the drive was looking like this and I was feeling better from the exercise.

I used the soil as we removed it to landscape the rear garden. I have in mind a simple design of two sweeping curves of grass bank which we lead the eye to the centre of the garden, away from the fences, and towards the view across the fields. I want something that's easy to mow and maintain. This went well and I was able to seed the grass on this bank just before we had some rain. The hexagonal slabs were reused from the from path.

Where the soil was cut away the bank was retained by turning the drive edging on its end with the concrete foundation to the outside. A trench about 30 to 50 cms deep enabled these slabs to stand quite firmly as a dry wall. They may not be the final solution but the reuse of these materials is very eco friendly.

This part of the project can rest until after Christmas if needed.

Long Term Value

We have moved 14 times in our married life so have quite a lot of experience in what does not work. I spent a lot of time making the last garden easicare and lawn free. Children loved it as they jumped from slab to low wall or paddled in the rills. Unfortunately their parents all wanted boring old grass for them to play on! The many beds of flowers were spectacular but not so easy to care for as I had hoped and some of the ground cover plants became very invasive. It really took a long time to sell compared with our other designs and we had to reduce the price. This time I want something much more simple.

I also find I am not prepared with the right information at the time we put a house on the market. This time I want to build the information and photographs over the years we are here so that selling is easier. A visit from Betty's friend June Shaw enabled me to do some work on this. Looking at our view it was important to know just what we could see in the distance and how far away it was. I had already identified Islip church about 5 miles away as a chuch with a tower. We then identified a church in North Kidlington with a spire which measured 7 miles on the Ordinance Survey. On a clear day with field glasses we can see much further in that direction to some distant hills and a large house. We now identified this as Cornford Manor 17 miles away!

I also want to find an estate agent who can promote the features we intend to build. This is surprisingly difficult. I can search for a holiday villa to rent that has a view but when I come to spend 1000 times as much I cannot sift properties on any criteria except price and location. This must change if eco-houses are to be marketed satisfactorily in future.

Bad News from the Planning 22/11/07

What a disappointment! Our application has been turned down. I suppose we were warned that Cherwell wanted to consider our application with next door as one project. We have not received the text of the refusal but David has emailed:-

The decision is on the grounds that the extension would overwhelm neighbouring Stonecroft and that it would reduce light to the property also. Various references to Local Plans etc have been given. I will scan the document and forward this to you.”

So much for preference being given to applications including eco features. It just does not happen!

David also says he has been invited to meet the district architect to discuss modifications which may meet their requirements. However 3 weeks later we have not heard about any meeting.

We were encouraged to learn from Kevin and Sue Geering, on the other side, that their application for an extension was turned down after objections from neighbours in Marchwood, but allowed on appeal.

We cannot even start the appeal process until we know what the outcome of David's meeting with Cherwell is. Then it takes 4 months. So much for action on Climate Change.

The documents 21/12/07

t last we have the actual documents by email and they are worse than we thought. The grounds for refusal are as follows:-

We found out soon afterwards that Fran's planning application had also been refused on the grounds that it was overbearing Marchwood!

All has gone quiet now for the holidays. However we seem on good terms with Fran and she has suggested that we should get together when our family return to Lanzarote. I suppose we should have taken the advice of the planning department and submitted the two plans for joint consideration to avoid this problem.

So much for the preference given to eco-friendly development!

Talking to the planners 04/01/08

I spent today trying to understand what policies C28 and C30 of the adopted Cherwell Plan might be without success. I could not find them online using the search facility on the Cherwell website. I posted a question to the help line so hope to get an answer soon.

I phone Mr Paul Ihringer at Cherwell and he kindly phoned me back when he returned in the afternoon from site. He explained that there were few problems with our application and suggested we reapply jointly with Fran. They would make a condition of any approval that both plans were implemented at the same time.

He said there were no problems with the size of our proposal but it was the style which conflicted with Fran's plans. By getting the latest copy of Fran's plans online we could see what he meant. She had changed the original concept incorporating bold features for a more traditional appearance with rectangular windows.

He recommended we get together with Fran and the architect to resolve these differences.

On the phone to David, he agreed to meet Paul Ihringer to be clear on his exact meaning and would then discuss with Fran what we could do, while we are in Cyprus for a week.

David advised we should only consider appeal as a last resort because of the cost and the delays of between 20 to 40 weeks that would result.

Learning about Planning 05/01/08

We have been hearing from several sources that a house half a mile down the road was also being built incorporating energy saving principles. I plucked up courage today and knocked on the door. There I met a charming couple in their 30's, the Greenslades, who have very similar ideas. They are building a new house behind their bungalow and it seems to have taken quite a long time. I wanted to know how they found Cherwell planning.

They said they had had great problems with a former planning officer and had been refused on the grounds of the view from a footpath and the location of the property. Cherwell had claimed that the property was not in the village of Horton cum Studley and so would be refused planning.

An appeal required the services of experts, cost £5000, and took more than a year to resolve.

We really don't want to go that route if we can help it.

The Greenslades are also planning to use Ice Energy for their ground source heat pump and have an air exchange system that is designed to change the air in all rooms every 2 hours. They have decided to add PV solar at a later stage when it becomes more cost effective.

We agreed to keep in touch.

ClimateX again 15/01/08

Back to work with ClimateX again and the first task was to enter the details from the feedback forms from the Open Eco-Houses in November. This was very interesting as I was not able to attend the weekend myself. Not everyone completed a form so it was estimated that in total 1200 visits were made and the results were very favourable. A full report can be seen on the ClimateX website.

The next job was to help to prepare for the follow up meeting on 17th April. This will enable those who want help with their eco-plans to meet specialists, architects and suppliers. It will also help them to form local groups so they can compare notes and support each other.

It looks as though there will be about 25 tables providing information in Oxford Town Hall and a meeting at which those who have Ecovated can tell how they got on.

What a pity I shall be away and miss the event.

Meeting with Architect 19/01/08

David suggested we meet together with Fran to decide how to apply for planning permission once more. As the designs were not considered coherent we would need to become more traditional or Fran's plans would need to become more modern. The plans would then be submitted jointly with an undertaking they they would proceed together. He presented two suggestions which are illustrated below.

The modern plan

The roof of Stonecroft is extended down to the left to meet the garage of Marchwood and the 2 triangular windows harmonise the designs.

The Traditional alternative

The plans were discussed for two and a half hours. Fran could see no way to accept the changes needed to permit the modern alternative but we also did not like the window slits on the first floor. Fran agreed to study the alternatives once more.

David's next proposal 23/01/08

oday David phoned to say that he did not think Fran would ever accept a modern appearance for the properties so he had prepared a traditional alternative which he would email to us. This duly arrived.

The line below the plan shows the view of the frontage from above.

Now dormer windows both sides gave the two properties a prettier look but the solar panels would be reduced from 14 to 10 although David had found some panels that appeared to be 15% more efficient.

In discussion Betty and I felt that we did not like solar panels spread over 3 roof surfaces so we proposed removing our dormer and raising the roof line. The would probably mean a complete reroof to give equal pitch front and back.

Fran may wish to raise her gutter level to match and add headroom but we shall see!

Google Sketchup

It's getting quite difficult to see how the roof lines are affected by these changes so I thought it worth while to try out Google Sketchup to construct David's plans and our modifications. 8 hours are available on a trial basis after which you have to purchase the program for $350. 8 hours taught me I needed more time to learn how to use the program but I did understand the problems a bit better.

This was the best I could do in 6 hours after using the online tutorial. I managed to do a little more on someone else's computer to try some other designs which I also sent to the architect. In retrospect, a mistake!

Starting again one year later

29th January – A New Start

David Foale today phoned to withdraw from the project. After discussion with his family he has decided that the work has become too stressful and he is no longer willing to work to reconcile our differing needs and the Cherwell requirements. Wow! Quite a surprise, further delay, but a new opportunity. I asked whether he would consider taking his original design to appeal without trying to co-ordinate the two requirements and he said he would let me know in a day or two. I have not heard 2 weeks later.

Today, 14th February, we met Michael Gregory once again. In spite of the history he was willing to take on the project and appeared to understand the situation very well. We agreed similar terms and he requested a letter of appointment in which we set out our priorities and wishes. He asked us to contact David as a courtesy and for use of his drawings. He would not have much time for the next couple of months but would give the project some thought and sketch some ideas.

I wrote a letter of appointment setting out my priorities and thought I should be clearer on the parameters for solar generation. I looked up the PVWatts web site again and compiled the following table comparing the theoretical optimum generation with the roof lines we were likely to consider.

Table produced from PV Watts website Output from 12 panels 1.2 x 1mt each


Tilt deg

Azimuth (180=S) deg

KWH est.


Garage roof




Not allowing for tree cover

Theoretical Optimum




For comparison

Optimum with sun tracking


2 axis sun tracking

Concealed flat roof




Panels inclined to South

Drained flat roof




Panels inclined to SW side

Panels on SW side wall




Side roof pitch 1




Theoretical Optimum pitch

Side roof pitch 2





North Facing Roof




Just the ambient light

Hourly output estimates indicate that early and late sun generates minimal electricity.

The best roof for us is side facing at 25 to 35 degrees but any Southerly roof is almost as good.

I am now looking at 18 panels on the side at a pitch of 28 degrees which should give 1725 watts.

Marvellous Eco-Build Exhibition this year

Last year we were disappointed at Ecobuild. The exhibitors seemed to know very little about the global problem and their suggestions bore very little relevance, on the whole. Bison, for example, were not aware that cement was responsible for 1/6 of global emissions of CO2. They had no plans to use other materials in their products. A government representative explained that the new build planning criteria were to be tightened but noted that 70% of the houses expected to be in use in 2050 had already been built. We had no difficulty in reaching every relevant stand in the 3 hours plus one seminar.

This year there were more free seminars and they were exceptionally good. We could not get to the one we wanted but enjoyed a theme of 3 seminars relating to the legislation that will make all new homes zero carbon by 2016 in England. Several speakers encouraged us not to wait but to get as far as we can now. U-Values of 0.15 were now possible for walls. We learned about German rubbish reprocessing, the EON project for infilling with beautiful eco solutions, an EcoPlay Toilet which stores and recycles used bath water for £2500, and the Tarmac green building products.

We did not get any details of the stands in advance, just a list of names, so it was difficult to select those which were relevant. On the other hand almost all the stands were relevant and it was impossible to get round all those which were of interest. Some we just collected literature or swiped our badge to receive literature later.

It was very encouraging to find more turnkey suppliers like Better Planet who would select a range of technologies and install them to work together. This links well in theory with the experience of the Oxfordshire Ecohouse owners who, when contacted recently, would not recommend the builders they used previously for further work. Better Planet also offer a more advanced wind turbine offer of the Swedish Energytower. I think it's time to get a quote from them. Oh dear! Their web site has been hacked by Islamists in protest to the publication of jokes.

Other products I must follow up are

        1. Tradical Hemcrete – better than zero carbon building to reach levels 3, 4, 5, and 6 with lime and hemp.

        2. Celina Klinker brick and stone slips for facing to blend with existing materials

        3. Clan Products Passive House achieves energy saving through controlled ventilation

        4. Energist – sustainable energy solutions, project management

        5. The Ventilation Window – unique ventilating windows system

        6. Ventaxia Ventilation and Central Vac systems

        7. Sunpipe – natural light for difficult areas and combined light and vent for bathrooms approx £700

        8. Daikin heat recovery ventilation

        9. Incana Italian decorative cladding

        10. Accoya – high performance sustainable windows and doors etc.

        11. The Green Wood Company – chestnut joinery from East Sussex

        12. Quadlock – wall structure road to zero carbon – seems to include a lot of concrete

        13. Internorm – passive house doors and windows to 0.71 U value triple glazed

More Google Sketchup

Google SketchUp has me hooked. It really is excellent for getting a good idea of the shapes from plans. You can make it as accurate as you wish. I have improved on my earlier attempts and have become quite fluent. I loaded it onto 3 computers but eventually ran out of time just when we were in the middle of making some important choices. I just had to buy it, even though it cost £301 including VAT. I'm sure I will save more than that during the course of the next few months.

In theory you could plan the inside and the outside of the building on the same model but this has proved too difficult for me, so I have prepared floor plans and filled these with scale furniture. These dimensions have been carefully transferred to the external model making sure that windows etc. are in the same places. I have just sent the results to the new architect to see what he thinks but I have not heard back from him yet.

Planning Application for Driveway

I also used Sketchup to apply to the local authority planning department for permission to make another entrance to the road. This will improve the appearance at the front and make parking more convenient. I had written to ask if we needed planning and was told that because the entrance being reinstated accessed a classified road it would need planning permission. They recommended I used the online planning application software on and it proved very easy to use.

As I looked through the questions it was clear I needed plans of my proposal with a scale and dimensions and photographs to show the situation. I also needed a plan of the trees and bushes that were near enough to fall onto the property! This is an example

It was fun to do so we just hope it will be successful. At any rate we will hit any snags before the main work starts.

Much Longer than we anticipated 25/03/08

Here we are in our second year in Marchwood and no further forward then when we arrived. Betty is very discouraged when she thinks about that, but we enjoy living here and are learning something new all the time. I have been working out exactly what we can see from the front and the back of the property. At the back, when it is clear and in the morning light we can see 13 miles to Cornbury House, an ex-royal hunting lodge in a country park on the skyline. We went to see it the other day but could not get very near. We have also identified communication masts at Leafield about the same distance away.

From the front drive we have identified Brill and in a good light can see the famous windmill through binoculars 3 miles away. It makes a view much more interesting if you know what you are looking at. Good preparation for that vital estate agent's leaflet!

The more we learn about the process the more we find others who have taken much longer to bring their plans to fruition than they expected so patience is the word. We are making good use of the delays to learn more about zero carbon methods.

Thermaskirt is a product worth exploring

An interesting product Betty discovered was the Thermaskirt which is an aluminium skirting that replaces radiators. They have quite a good web site which enables you to plan each room separately and get a quote for the components. They then email you making suggestions to work better and save money.

We needed more area than they recommend because we are hoping to run the ground source heating at a lower temperature than a conventional radiator system. I have emailed them back for some advice on this and for the watts output per metre of skirting at various water temperatures.

The cost of our 4 bedroom 1 bathroom 2 ensuite plan comes to £4401 plus fitting which we could do ourselves perhaps. We could probably cut this down a bit when we have the final plans. Betty would like to be free from radiators but I suspect underfloor heating would not cost more than that. We shall see.

Returning to the diary after 8 months break

How time flies! We went on holiday for a month and then returned to work on the plans again to resubmit them to Cherwell.

Michael Gregory helped us to get back to the fundamental reasons for the failure last time. Our neighbour Fran had felt overwhelmed by the large mass next door and compelled to extend her own property to compensate. Cherwell had agreed with her viewpoint and also pointed out the loss of light our development alone would cause. We were disappointed that Fran had not made this more clear to us before the application went in but had to agree that she had a good point.

Michael was not keen to just tweak David's plans and we too felt a fresh start was desirable. He cut down the mass at the front to blend with the street scene and make it more attractive. The space lost at the front was gained by making the rear extension two storied.

When we showed this to the neighbours their reactions were quite interesting. Kevin on one side was happy from his point of view but felt we were likely to be paying quite a lot for the extra space we had gained. Fran was against development on the second floor at the back. She said she was loosing a view at the front and did not want to loose a view at the back as well. Planning would probably not have upheld this as she would not be able to rely on views across our property.

To give a clearer understanding of what Fran was loosing we took photos from her bedroom window at the back and places stakes in our garden marking the corners of the proposed extension. We also used Google Sketchup to model her view before and after.

Discussions with Michael, our architect, on costs indicated that the we might exceed the £100,000 budget we had set. He was in favour of planning for the full extension and getting quotes for the work in the stages we could afford. We felt this was conflicting with Fran's wishes unnecessarily if we were not able to afford the full plan. It could also lead to further delays if she raised objections.

In the end we asked him to redraw the plans to allow only a single story extension at the back and adjust the rooms to achieve a more modest 4 bedroom 2 bathroom layout. This is what they looked like.

Now the plans are in we have 8 weeks to work out how the inside will be arranged. This includes the cupboards in the new kitchen to the ground source heating distribution inside the house. While we have been attracted to the Ice Energy systems they do not appear to include any advice or recommendations for inside. We started talking to the local merchants and Johnsons in Cowley near Oxford has an excellent display by Worcester Bosch of their ground source heating systems. They also showed solar hot water systems and a great range of kitchen and bathroom fittings. A very helpful assistant was able to explain their exhibit and provide the names of installers who had been working with the system.

One of the exhibits gave samples of the Upenor underfloor piping system so we took details to see how Upenor would design our system and what is would cost.

We are still concerned that an underfloor system will need the concrete floor to be dug up so that we can get sufficient insulation under the heating pipes and sufficient screed above. We have considered putting pipes in the walls or ceilings or changing to a warm air system which we found very good 35 years ago.

We also learned about the BuildCentre near Swindon at which some hundreds of suppliers have exhibits. Entry is free and we suggest several hours are needed to get full value from the show houses and building systems on display. While it is not all low carbon there is an adviser who will discuss your project and suggest the options which will work best. He was very well qualified. He warned us about ground source suppliers who wanted to draw more that 20 watts per square metre from the ground and said that the sun would not then be able to replenish this heat during the Summer. Our plot of 26 metres by 12 metres or 312 sq metres should be able to produce 6kw which should be sufficient if our insulation is good.

He seemed to prefer air source heating as this did not have such a limit and would cost less too. I prefer ground source because it multiplied the electricity used by 5 to 6 compared with 3.5 for air source, so reducing running costs and saving energy.

The science advances - 12/10/08

I have just started reading Climate Code Red after meeting the authors at the Operation Noah Board meeting. I have always suspected we are asking the wrong questions and so setting the wrong targets for global emissions. This meeting and this book confirms my fears. We have to start with the question “What is a safe level for the world temperature?” rather than “What temperature are we bound to reach before we can act effectively?”

If the answer, as they suggest, proves to be 0.5 degrees above the pre-industrial level, or about 0.3 degrees below the present level, then we will need a three pronged attack to

These steps are giant sized compared with anything being discussed by governments currently. We will know we have succeeded when the polar ice starts to thicken again. We dare not gamble with the planet or let warming get out of control.

Heating Plans

Our plan to achieve zero carbon is very simple. We will use electricity and buy green electricity. This action by enough people will in turn encourage the government to develop wind and other renewable power sources rapidly. This would be very expensive for us unless we can minimise the energy requirements of the whole house. We will try to do this with fuel efficiency and super insulation. Insulation I will discuss later by here I will report our struggle for energy efficiency.

We have chosen electricity to deliver ground source heating because any other methods will involve some burning. We believe burning will have to be banned, with very few exceptions, if emissions of carbon dioxide and other greenhouse gases are to be brought to low enough levels.

Ground source heating will multiply to input energy by 5 or 6 if it is run under ideal conditions compared with about 3 for air source heating. We want to get as near the ideal as possible and we understand that the output fluid temperature that heats the house is the most significant factor. A lower output temperature can be set if the emitting area is large enough and efficient enough to emit the kilowatts required.

The first information from our architects was that we needed to remove the screed and the concrete base of the house to enable us to excavate below and insulate before laying the heating coils. The excavation was at first costed at £3,000 but Michael said this was very optimistic and did not include restoring the damp course and foundations which would bring the cost nearer to £12,000.

We then started exploring warm air heating as a means of distributing heat from warm water. We have enjoyed this in a previous house and have been pleased with the quick warm up compared with radiator based systems. Of course there is a big difference between a gas boiler's high output temperatures and a heat pump's low output temperatures. We have not been able to find any working examples of this method.

A fan assisted radiator is the kind of equipment which could be the basis for such a system. Perhaps a bank of several might be used, concealed in a false ceiling. Betty is not keen on an untried experiment unless there are adequate safeguards.

Meanwhile some friends at a wedding claimed they had seen heating coils laid over an existing base including insulation which did not raise the floor level too much. We had seen this from Uponor at exhibitions and when we got in touch they claimed their System 12 could achieve underfloor heating with only 45mm loss of ceiling height. This looked feasible so we invited them to visit on 30th October. It was a very informative meeting as the local sales manager had considerable experience of installing underfloor heating in his own home. He confirmed doubts which had been expressed by the advisor at the advisor at the Build Store in Swindon about the adequacy of our garden. We asked whether we could be a demonstration site for his system and encourage visitors by taking additional measurements of temperatures in the ground and output power. He agreed to look into it but said we would get very few requests for a visit.

He said he would ask a partner company to quote for the ground source part of the system and they would quote for the underfloor heating. We have not yet had a quote from either.

Learning where you can.

Betty is an avid watcher of all the renovation programmes and we gain some insights of what is possible and what can go wrong. We learned how costly it can be to neglect to consider the neighbour's rights, and resolved to apply to Fran in plenty of time, before we need to work on or over the party wall between our two garages. Notes provided by Bromley Council on this most important question are reproduced in Appendix 1. The notice we need to give is 14 days but if we do not receive a reply a dispute is deemed to have arisen which can drag on for months and become expensive.

Most of these programmes can be rather misleading. Either people have such grand ideas that the results are quite impractical or their buy to let plans are poor but they still make a profit because of the rising market. As of mid 2008 the market has turned down and a net profit on our project will be unlikely. This does not totally depress us because we should be able to buy a smaller house at the end of the project and still have some savings to live on. We are rather depending on selling when there is a premium for low energy housing. Perhaps there will be fuel rationing.

Planning Approval 30/10/08

At last we are on the way! Betty is over the moon. I am a bit cautious as there are a lot of decisions to make and we will soon need to put our money where our mouth is!

Worst of all, we have been unable to choose between the various options to heat the house. This is now urgent as Michael has started working on the Building Plans.

Ice Energy

Ice Energy have been our favourites for heat pumps from the beginning and we thought it was time to see one of their pumps in action so phoned and visited their showroom in Eynsham on Monday 3rd October. It is an impressive but not lavish operation which suggests they know how to operate profitably without waste or excessive charges. They have completed 2000 installations and are the largest suppliers in UK. They will not survey a site until planning has been granted and then only when an order has been placed for a heat pump. This must be to cut down on expensive time wasters.

Adam Cusick, who I had dealt with on the phone for the past year and found very knowledgeable and helpful, showed us around. We were pleased with the pump in action. It was a little noisier than a refrigerator so would be heard at night in a quiet area. Betty thought that would be OK. We decided on the integrated unit including a 180 litre storage tank rather than the separate 300 litre storage tank. When we discussed the garden area that would be needed it would appear we are close to the limit for the looped coil system. We have just enough area at present behind the house but allowing for the new extension and a 3 metre barrier between the collectors and the house we only have room for the compact collectors. These need to be 2 metres wide and 16 metres long and we would need 2 of them for the 7KW Heat Pump.

We mentioned our concerns about freezing the ground and Adam showed us the data the heat pump collects regarding the input fluid temperature and the lower temperature at which the fluid returns to the ground. He said the system would operate at temperatures well below zero without any problems but did not offer any data on the efficiency at those temperatures.

They sent a quotation almost immediately confirming their estimates of £8445 for our system and this would be reduced by a grant of £1500.

Looking at the quote and specification it would appear that the IVT Greenline 7C heat pump achieves 7.3 kw of output energy for 1.6kw of input energy when run at 35 degrees C giving a ratio of 4.56 which is not as good as I had hoped. At 50 degrees the ratio is 3.17 so we would need to run at about 25 degrees to achieve the 5.5 that I would like to achieve. I would like to be able to check this.

There did not appear to be any data logging capabilities so we would never know what efficiencies we had achieved or how many kilowatt hours of energy we had obtained. This always seems to be a weak point when describing the benefits of a conversion. People say “We are much warmer for the same cost” or “We are using 60% less energy than the average house of this type” which is not a very precise result. We want to know the kilowatt hours we have used to maintain an excess temperature over the surroundings so we will need to log the inside and outside temperatures continuously. We have found a small logger that will hold 30,000 measurements and then download them to our laptop so we must find out the cost.

Upenor Visit 30/10/08

A representative of Upenor visited us in response to our request. He brought his Sales Manager who had installed to Upenor pipe in walls, floors and ceilings in his own house with great success. It was good meet someone who believed in his products enough to use them and we were encouraged. He explained their System 12 for renovations in which they lay 12mm pipe of very high spec. in an aluminium carrier for conductivity. This only needs 30mm of high performance insulation underneath which was designed for the space industry and on top marine ply and tiles or wooden flooring. This results in an increase of only 45mm in floor height which would not affect our ceilings and doorways too much.

We asked them to quote and we had to remind them several times before the quote arrived. It was for the components alone and was £5000 for each floor! Half the cost was the aluminium carrier! They had also looked doubtful about Ice Energy heat pumps but would not recommend anyone themselves. They went back to the Johnsons who asked Solar Solutions to call.

Solar Solutions 12/11/08

Paul Claridge from Solar Solutions called but straight away said there was no one better than Ice Energy who had installed 2000 systems and had experience of every type of soil and situation. As he was there we took advantage of the opportunity to consider solar hot water to avoid using the ground source to heat water for the 6 months of the year when heating is not needed.

He followed up with a quote for £3600 for a 30 vacuum tube system which we thought was very good. Unfortunately the adaptation to the Ice Energy system to store solar hot water would cost another £1000. This would be £1400 for a 300 litre tank with additional inputs less £400 credit for the integral tank.

We had ordered the Ice Energy system but put this on hold until we could make a decision on solar hot water.

Finding the Finance 18/11/08

Last year we had gone shopping for a mortgage thinking we would raise about £80,000 for 5 years to allow us to enjoy the improvements and then sell the house and move to something smaller. When our planning failed these arrangements expired and now was the time to start again. Short of time before we went away, and in the credit crunch, Betty suggested we try on the Internet to see what they could offer. Our plans were now to borrow £50,000 over 5 years. I am now 73 but have maintained a good credit rating which now stands with Experian at 999.

With all the details on the internet they came back quickly saying they thought we could get £50,000 for 5 years from Northern Rock! This did seem strange as Northern Rock had recently been bailed out by the government because of a run on its deposits and some unwise investments. However it is now guaranteed by the Government so is worth a try.

At the same time our daughter Valerie suggested we try her broker who has been very helpful. We told him the situation and asked him to come up with his best suggestion. He came up with Northern Rock too!

There may be some difficulty as we have gone away before we received the application to sign and our emails have not been answered.

Drawing up the Building Plans

We know the next step is to get building plans approved but we don't know quite what this entails. We hoped our architect was starting to do this but it seems not so we requested a meeting the day before we went away. Michael was not well so this did not happen but we had a long chat on the phone so are now clearer.

We had to approve the method of construction for the new parts and decided on rendered walls to contrast with the Bradstone existing building. This provides a pleasing variation but also enables us to achieve higher standards of insulation. This is most important as both extensions have 3 outside walls.

Now Michael hopes to complete and submit the drawings in January when they will also be available to obtain quotes from builders.

Climate Code Red – David Spratt and Philip Sutton

I have now reached the end of the book and am impressed with the common sense viewpoint it reaches. The science of Climate Change had been unable to predict the substantial loss of the Arctic Icecap in 2006 and 2007 so did not have the safety factors built in that one would expect. Climate Code Red asks the right question. What is a safe temperature for the earth and how quickly can we reach it?

They conclude that we do not know that answer but that a temperature which puts the ice cap in danger is too high already. The solution is likely to need simultaneous actions to:-

  1. Rapid reduction of greenhouse gas emission to near zero

  2. Extraction of greenhouse gasses from the atmosphere

  3. Cool the earth artificially until these actions take effect.

In this scenario some rationing of carbon seems inevitable and there may well be power cuts or 3 day week events to enable the transition to sustainable energy in sufficient quantities.

We lived through the post war power cuts and the 3 day week and have learned to value emergency fall back planning. Discussing this with Betty we agreed we wanted to make the house as future proof as possible.

What happens to ground source heating when the electricity goes off? Disaster! No heating, no cooking, no lighting, no refrigeration. This is no worse than most centrally heated houses of course as all systems have electric circulating pumps and safety cut outs.

What happens if we are rationed to 1 kw of electricity because of shortages? A further set of problems.

We have started to look at solid fuel as a back up system, perhaps with a 12 volt circulating pump. Once again how would the hot water from a log burner integrate with our Ice Energy system?

Evergreen ST1020B Multifuel Wood burning Boiler 05/12/08

Most multifuel stoves seem to be expensive luxuries which would be inappropriate to our project. At last, on Ebay UK, I ran across the above stove at £750 plus £50 carriage from Cheshire which seems to have the character and function we need. It is supplied by the “thegreenercompany” and I think it is worth going to Cheshire to see it. I also found a 12 volt circulating pump for £50 from easy_flow_pumps drawing 1.3 amps at 15 volts and operating down to 9 volts. Will this be sufficient to provide emergency heating? For how long? Will this integrate with the Ice Energy system?

Back in UK now and following up with Ice Energy who feel it would be better to keep the emergency system separate from the system that would operate while the grid is working.

I have tried to plan the location of the wood burning stove using Google Sketchup.

would prefer to have space to the right and left to store logs but this would involve a major extension of the chimney breast outside. This is not worth doing as the modification of the existing fireplace could achieve almost as much. I am also getting cautious about fitting a fireplace without the advice of a local supplier. What insulation and fireproofing is needed?

Parkray have a good reputation for many years and their local stockist, Mobbs, has been very helpful. They have clarified some points and recommended a local specialist, J. R. Plumbing and Heating who are coming to see us. The Parkray Consort 7 looks about right. We have planned a very plain setting with the stove about half out into the room to enable the air to circulate round it.

The marble base to the current fireplace can then be retained and the edge to the recess cut from the existing marble back of the fireplace. There will be no mantle shelf.

I do love Google Sketchup!

Parkray have explained that the boiler should not be fitted before the pipework and storage was ready as we want to use the fire as soon as we can.

Back from holiday 10/01/09

Well we're back and raring to get started. We emailed Michael to fix a meeting. No reply so phoned to find he was laid up with the flu' and no energy for anything. He thought he might have a slot for us in mid February, depending on his health, to complete the building drawings. He had contacted a structural engineer to determine the sizes and positions of the beams needed, as he takes some time to respond.

It is also freezing and we ran out of oil just keeping the house from freezing while we were away. Wow, the insulation is dreadful. Now we have to wait 10 days for an oil delivery!

Betty is very disappointed we will not even get quotes until March. I began to think what could be started in advance. Some of the work on the older part of the property could be done before the main work started. I made a list

The ground source survey

Cavity wall insulation

Loft insulation

Updated electrics and replacement of dangerous wiring

Emergency lounge heating, multi-fuel boiler.

Ground Source Heating

Discussions with Adam Cusick at Ice Energy have continued. I am not keen to pay an extra £1400 to replace the slinky coil underground collectors with compact collectors which Adam says will fit more easily into the garden. I am told the compact collectors distribute the cold better in the garden but they cover a smaller area so this is difficult to understand. I want the survey to be based on a slinky quotation but Adam will have to discuss this with a technical expert. This is my plan for the slinky. We will see what the experts think.

avity Wall Insulation

I am over 70 so wrote to Cherwell to see what they had on offer for insulation. Nothing apparently except for those in rented properties. They recommend Cocoon as a service for providing insulation at a 50% discount. I emailed them and await a reply.

1950 Living Standards Tomorrow 15/01/09

The oil has run out and we are using a portable convector heater to keep the room we are in a little less than freezing. In the evening we have a propane gas fire and this gets our lounge nice and warm.

We are making this an experiment in 1950's living because tackling climate change may involve energy rationing which may well turn the clock back for many. I remember the 3 day week, electricity cuts for 3 hour periods, and the safeguards we adopted in case it happened again. Dual electric and gas cookers. Always a camping stove ready to cook a meal.

I remember in my early working life the UK regulations said the workplace had to be 60 degrees for clerical workers. We tried keeping the room we were in at about 15.5 centigrade. We needed more clothes but Betty found it really painful and never got warm. The worst was the unheated beds during below zero temperatures and we never got warm.

Cavity Wall Insulation 27/01/09

It does seem strange that I have not been able to find a comparison of the cavity wall products based on their thermal efficiency. I am not so interested in the 'natural product' arguments as I feel they cut both ways. I am interested in the best performance for my money: as once the insulation is in there it cannot be changed.

I spoke to Jo Hamilton at ClimateX today to ask her advice. She recommended the information made available by AECB and I looked this up. They provide a good general guide to achieving the standards of energy efficiency up to the gold standard and hint at the suppliers of the products but do not provide the hard evidence of comparisons I was looking for.

I am helping her to develop open eco-house visits and shared information in Oxfordshire and her new plan is to cooperate with other eco-house groups in UK to pool ideas and resources. Brighton seems to have done well and there is a national register developing at both COIN and The Sustainable Energy Academy. Their web site at looked very promising.

The presentation of each renovation was particularly helpful. The summary provided the main features and led to contact details and further useful information.

I was able to print out 7 scenarios from our existing heating and insulation to a high spec. solution and compare the carbon emissions and savings. I could discuss these with Betty in an interesting format. The results appeared to indicate that for our property we should concentrate on loft and wall insulation to save money and ground source heating to go zero carbon. Nothing else matters too much.

The only query we have is that they calculate our uninsulated house will cost £1700 to heat when in fact it costs in the region of £900 per annum, even with an aged oil fired boiler. Perhaps the calculations are based on 24 hour heating but we only heat during the day when we are here. I must look into this.

Why I can’t compare U vales - 31/01/09

Today I found out why I am having great difficulty in comparing the U values for cavity wall insulation. Wikipedia gave me the answer and provided a lot of the values I was looking for as I have reproduced in Appendix 1.

The US Standards Agency has legislated to enable the consumer to know the R-value of the insulation being put into the walls but the trade appears to avoid the spirit of this legislation in ingenious ways.

Looking into the detail for cavity wall insulation it would appear that Rockwool and Fibreglass loose fill are at the lower end of the insulation scale at 2.5 to 3.7 with Polyethylene foam. Icynene loose fill is rather higher at 4. Then comes Urea Formaldehyde foam between 4 and 4.6.

Phenolic Spray Foam is substantially higher at 4.8 to 7 R-value. Closed Cell Polyurethane Spray Foam varies between 5.5 and 6.5 while Polyisocyanurate Foam varies between 4.3 and 8.3.

This independent information makes it much easier to discuss the merits of various types of insulation with suppliers. I wonder why the performance of some insulation is so variable while Icynene, for example is rated at such a reliable value of 4.

Changing Climate

29/01/09 and it is time to digress for a moment. When we started this project 2 years ago the general understanding was we needed to achieve reductions in carbon emissions in the region of 60% and the climate would recover before serious damage was done. Some said the developed world should cut more to allow for the developing world. Climate models were used by the IPCC scientists to predict very modest changes by 2050 which they assured us would not be too damaging.

And we believed them!

2007 changed all that! The Arctic Ice Cap shrunk suddenly to its lowest level in modern times 30 years than the scientists had predicted. In April 2007 the news started to break. Scientists at the National Center for Atmospheric Research pointed out the difference between the model forecasts of icecap decline of 2.5% per decade and the actual between 1953 and 2006 of 7.8% per decade.

This is their graph

A bit late to notice you might think!

Something is happening that has still not been explained. A factor is at work which has not been built into the models. As if to underline the problem, 5 months later the bombshell struck.

A drop in the September ice extent 10 times greater than the average of the last two years! 23% less than the previous lowest extent in 2005.

The news media have found many outcomes for polar bears, shipping and the oil industry but they have missed the two most important conclusions.

  1. The sudden rapid loss of Arctic Ice is caused by factors not evaluated by climate models; so climate models are an inadequate basis alone to assure us of a safe climate. The tipping points which scientists fear are already happening and are less predictably than they ever supposed.

  2. All plans and forecasts based upon climate models are now out of date and suspect. We only know for certain after an event has happened. Plans based on keeping the global temperature increase below 2 degrees are totally obsolete.

  3. This has happened at a global temperature increase of only 0.85 degrees. What could happen before 2 degrees are reached?

Academics, climate movements, scientists and governments are in complete disarray. Most have not noticed the difference, even though 2008 matched 2007 Summer ice extent. Most continue to find ways to solve the old problems and ignore the new.

One exception I found in 2008 is the book ‘Climate Code Red’ by David Spratt and Philip Sutton. This is an amazing book is closely reasoned and covers the science, the dangers, what is not working and what needs to be done.

It makes a case that we should be seeking a safe climate at any cost. We should not start from a compromise of what is considered practically possible. In times of national emergency, like 1939 for UK, every resource is diverted to serve the war effort, failure is not considered, and cost is the least important factor.

It shows that delays will increase the total cost and the damage which is inevitable.

It proposes a drastic cut in emissions enhanced by a massive programme to capture the carbon already emitted. Even this will not act quickly enough, they say, so some global cooling will be needed.

While I agree with their logic and cannot fault their reasoning I fear governments will not act in time to do any of these things. What can I do? I think I must prepare for the best and the worst.

I will campaign for a safe climate, and am glad to see many Australian charities and Greenpeace USA are already giving this their priority. I will prepare for energy rationing, as any action by government is likely to include drastic action too late.

I will also continue to try to be a typical house conversion for the 21st century. I believe the government needs 1000 examples of zero carbon eco-living so that it can set its standards and impose its rules for the emergency. Zero carbon eco-living seems to us quite possible simply but ground source heating and buying green electricity. The government then needs to do its part by making all electricity green!

I will continue to measure before and after in as much detail as I can so that the everyday householder may avoid my mistakes and not have to spend the vast amount of time in research that I have spent.

End of Part 1

Part 2

Further Research

Betty is getting more and more frustrated at the slowness of the project. She watches “Grand Designs” and similar programmes and wonders how they can progress so quickly compared with us. I am feeling thankful that we have the time on the way to get things right and to understand why.

For example our efforts to compare roof insulation resulted in the information we obtained in Appendix 2 so the way ahead looked clear. All we had to do is find a supplier of one of the high R value types of insulation and have it applied. Spray foam looked high on the list for R values and we hoped a chat with a company who applied the foam might allay our architect’s concerns about too rigid a roof structure. We found Roofing Insulation Services who said their spray foam would achieve a U value of 0.26 if sprayed to the depth of our 100 mm rafters but with battens on the rafters we could achieve 0.20

We were expecting a cost of several thousand after our talk to Warmroof so a rough estimate between £1800 and £2400 sounded quite good. He also said the foam had 5% flexibility and a 25 year guarantee which seemed to meet the architect’s objections. We booked a visit for the following week to get a firm estimate.

Meanwhile we wanted to make sure this was the best for the money. The Celotex website was a help here. They have a U value calculator which builds the answer from the elements and air gaps you put in the roof. It is designed to use their products of course but you can substitute other products as long as you know their relative resistance. For example, our architect had used Triso Super 10 in earlier work and had also picked out a good supplier. The is a French product which has been available for some years made up from 13 layers of foil and insulation. It is only 30 mm thick but they claim it is as effective as 210 mm of rockwool insulation. We want to use the loft for storage so the space gained is important and the insulation value is even more important. As Celotex claims to be the equivalent of twice the thickness of rockwool we had our conversion factor. If we put 50mm of Celotex between the rafters, leaving air gaps of 25mm each side to eliminate condensation, and then the Triso Super 10, the equivalent of 100 mm of Celotex with battens and ceiling board the calculator shows a U value of 0.14. Pricing this up we can achieve a better result for £1100 of materials plus my labour.

I sent the little drawing below to our architect to double check. The roofing felt is a problem. It is the old fashioned non breathing type which means we should leave a 50mm gap between it and the insulation if the roof it to be used for habitation. This is sufficient to avoid condensation but reduces the thickness of insulation we can have between the rafters. As the loft will only be used for storage I reduced the gap to 25mm which the architect said I was entitled to do.

So I cancelled the visit from Roofing Insulation Services and did a last check on the competitors for Triso Super 10. There are two British ones which are a little cheaper and have slight variations in specification but we opted for the well tried but more expensive Triso Super 10.

I ordered the 50mm Celotex Tuff-R from at a cost of £16.33 per board plus VAT tax and a roll of Aluminised tape for a total of £402.36.

I have insulated a larger loft before using rockwool between the rafters and covering it with wallboard to make a workroom. That was an itchy business and I am now told I should not have stuffed the space so full as condensation may form and the rafters rot. I don’t expect this to happen unless the workroom is used on a regular basis. The only access is by the loft ladder so it is for occasional use only. It did make a difference to the warmness of the house though. I hope this time will be easier and better, though more expensive.

Today the Celotex arrived, only 2 days after I ordered it, on my preferred delivery day, with a prearranged phone warning 10 minutes before arrival. 3 cubic metres now dominate the garage that was already very full! Better than in the house though. The rafters are 360mm apart so I tried cutting one board into 360mm strips with a Stanley knife. It was rather a time consuming job but I cannot get 1200x2400mm boards into the loft anyway. It looks about 10 hours work just cutting the boards to rough size. Then we will see how they fit between the rafters. I bought a new dust mask for that job.

More Ground Source Heating Discussions 02/02/09

After another week Adam Cusack of Ice Energy can back saying that my drawing of trenches 1 metre apart would not be suitable as his technical colleague said the trenches needed to be a minimum of 2 metres apart but could be reduced to 80 metres in length if mini slinky pipes were used. A prepared a drawing on this basis expecting a prompt reply and a survey booking but I have heard nothing and have now sent a reminder 2 weeks later.

Everyone is so busy you would not think there was a credit crunch or recession. Bumped into Phil Munt, our proposed builder, today who says he is very busy.

Deciding on a stove 18/02/09

One thing we thought we could get ahead with was the stove. Mobbs had recommended their local fitter for the Parkray we had chosen but we needed a quote from him before deciding on the Parkray. After a couple of reminders and a complaint to Mobbs we have still not heard from him.

Meanwhile we found a new stove showroom, The Oxfordshire Stove Company, at Royal Oak Farm, Islip Road, Beckley with a good range of reasonable stoves which made us think again. The assistant said if we found a stove we liked on the internet they would quote for fitting it. We returned on Saturday to speak to the owner, Ian Bush, in the showroom where a blazing wood burner kept the huge showroom very warm. He offered to visit and quote for the installation but said we would have to have the existing gas fire professionally removed first. He gave us a gas fitter to phone for this.

Back at home we had another search of the internet for comparisons. The Stoves Online website gave a great range of stoves and a selector. It was not at all clear which models could be fitted with a boiler to heat our water. It was slowly dawning that we might have a ventilation problem too. It would be better to draw the air for combustion from the outside to avoid wasting our warm air up the chimney. Ian Bush had said not to worry as a wood burner used much less air than an open fire. We looked up the regulations and found that fires over 5kw need 500 sq mm of outside air per kw over 5. They also recommend a smoke test to ensure satisfactory burning. The Whatstove website gave reviews by owners of their stoves in which the Dunsley Heat was rated very highly by 2 owners with glowing reports.

Although we do not expect to burn the fire often our house will be more draught proof than most, so a direct outside air supply would be most desirable. This then works like the modern balanced flue gas boiler whose air intake and gases released are entirely separated from the dwelling. Most of the stoves on the internet do not make clear if outside air can be fitted.

An email enquiry to Dunsley Heat obtained a quick response that outside air connection could be fitted to any of their wood burners for the very reasonable cost of £60.80 plus VAT and carriage to total £79.79. Their Highlander 7 stove at £836.60 plus a 3kw boiler at £217 and outside air would total £1133 is our favourite at present. There are many cheaper fires like the Stanley Oisin from at a basic £499 which need some research before making a decision.

Conversation with Ice Energy 19/02/09

At last Ice Energy have approved our latest plan for the ground source collectors in the garden. We decided that the money saved could be used to purchase the larger 280 litre hot water tank which would give us the freedom to add another energy source like solar hot water if we can afford it. Adam promised to forward the new quotation on that basis and it arrived by email immediately. The total was now £8267.70 against which we could expect a grant of £1500.

We accepted it and booked the survey the next day.

DIY work in the loft 22/02/09

Cutting the Celotex seemed easy and resulted in little dust. The manufacturer suggests a thin blade of a saw or a sharp knife. I marked the proposed cut with a felt pen and the blade of my Stanley knife cut to about half the depth of the board and round the ends. It was then easy to break the board along the cut. The foil outer skin is then sliced with the Stanley knife.

With a couple of the Celotex boards cut to size I started to fit them between the rafters. Michael Gregory, our architect, examined the detail of the work I was proposing and approved. Cellotex recommended a spacer of wood to maintain the air gap between the roofing felt and the Celotex insulation. Michael suggested it would be sufficient to retain the gap with nails, and much quicker.

I tried this method and it appears to work well. The pre cut insulation often did not fit the first rafter space but by trial and error fitted one of the others. I prepared another two boards as before but with a sharper blade in my Stanley knife they cut much more easily. I had to spend more time trimming them however (with the carving knife) before they would fit. I decided to take careful measurements of the remaining spaces and make the insulation individually to fit.

The two boards took about 2 hours to fit and brought the total to about 10 hours. As this represents about 25% of the Celotex insulation work I can expect to spend about 40 hours on the whole of this stage.

The boards are kept in place by one or two nails until they can be sealed in place with Wickes decorators caulking at £1.16 per 300ml. I want to be able to achieve an air tight result.

Now I am about half way and I have found that the extra time cutting the boards carefully pays off with a quicker fit and less sealer required. I now mark the cut line carefully with felt pen, make the first cut with the Stanley knife and deepen it with an old lino knife. When it is broken along the cut the edge is almost uniform and just needs the back foil surface to be cut.

I fit one board to the ridge and another to the eaves leaving a gap which needs to be measured and cut especially. I tried to save material by putting two pieces in this gap on one occasion but it really needs to be a single piece. This is where a piece of 20mm trim would be useful to line up the 4 edges for a neat finish.

The Building Plans 27/02/09

Michael, our architect, contacted us to apologise for the delay and suggested that he could ask a colleague to prepare the building plans for him. We were a little cautious about this as our preferences might not be conveyed well to a third party. When I happened to mention this over the fence to our neighbour he said all his work was sent to Wales for the building drawings to be done and it was common practice.

Even so some issues occurred to us that might need to be resolved.

Eco-Build at Earls Court –Ground Source

Our main aim is to find a cavity wall fill that will give us a lower U value for the wall but we also want to learn more about ground source, new materials, windows and staircases.

We timed our arrival just right soon after the doors opened and went straight to the Daikin Theatre for a series of talks on ground and air source. Each speaker had an angle from the products he promoted but the chair was very good with remarks to keep the balance. The chair set the tone explaining that the EU was committed to the expansion of ground and air source heating from December 2008. The high efficiencies, long life and low maintenance make them key to the battle against carbon emissions. Clean and compact operation makes them highly desirable. The context was set by the EU move to adopt the Passiv House standard for all new building by 2015 where U values of 0.09 are possible for the walls. What happens to our present buildings?

The first speaker extolled the virtues of boreholes and ground source. High efficiencies or COP values of at least 4 could be obtained even on days when the air temperature was low. The higher initial cost of the boreholes could be absorbed in social housing or when neighbours got together.

He explained that efficiency depended on a higher source temperature from the ground and a lower running temperature for the heating system. A large area collector in good ground conditions ensures a good source temperature and a large area of good conducting under floor pipework keeps the output temperature low and the building warm.

His diagram showing the replenishment of the energy extracted from the ground was revealing. It showed little arriving from below and most arriving from conduction or the sun on the surface. He also spoke of the value of using the aquifers. It did appear that the population density in cities would make ground source heating, even with boreholes, almost impossible for the majority.

For those with a garden the slinky methods should be preferred. They advised that the owner of a modest garden should work backwards by calculating the available ground heat at 40 watts per square metre to size the heating. For example a 10 metre square garden could support a 10x10x40 watt heat pump = 4kw so the house insulation and heat recovery systems should ensure that this size heat pump would be sufficient.

The air pump expert extolled the low initial cost and flexibility of these units in every situation as boiler replacements. A COP value of 3.2 was claimed saving a lot of money and carbon emissions. A questioner pointed out that the electricity used was being produced from fossil fuels so the total carbon emissions were no better than from a good condensing boiler. The panel disputed the figures but agreed that the full benefits would not be gained until all electricity was produced from green sources.

In an aside it was mentioned that low temperature systems had to run at high temperatures once per week to avoid the problem of Legionnaires disease and other micro organisms. Something to ask the supplier!

The speaker giving case studies was disappointing as they all seemed to be Grand Designs with money to burn! It is a paradox that the spectacular savings of money are obtained by huge heat pumps heating poorly insulated buildings in acres of ground whereas the national interest is best served by a multitude of small savings in highly insulated properties.

The speakers recommended that the same contractor carry out the ground works, heat pump commissioning and under floor heating work for the best results. Heat storage was discussed as a topic for the future in the design of city wide systems.

It is desirable to replenish the heat taken from the ground. This can be done if the pump is the reversible type. The rooms are cooled in the Summer and the ground is warmed. This is discouraged nationally as it uses energy from the grids not needed previously.

Cavity Wall Insulation at EcoBuild

The programme made it impossible to trace cavity wall insulators by name at the exhibition. The list of wall insulators did not give stand numbers and the information desk did not have any reference material. We wanted something better than Rockwool so we tried the Energy Saving Trust stand for advice. The technical advisor recommended CIGA , who did not have a stand at the exhibition or INCA who did but did not cover cavity fill. We visited the Knauf stand and BASF who told us what we already knew, that all the fill materials had a similar performance. We also found a stand which said “don’t fill at any price”, but they were selling external insulation products!

CIGA were busy the next day when I tried to phone them and their local registered installers, Instafoam and Fibre Ltd of Wokingham were unable to discuss alternatives to Rockwool and beads. They came back to me to say they had not used any other method for the last 12 years. I emailed CIGA and they said that to two methods on offer were the only ones available. He said there was little to choose between them for thermal efficiency. So end of the trail I think. I will order the cavity fill using the Knauf material from our local installer.

Staircases and Windows at EcoBuild

These were often on the same stand but none of the manufacturers provided any idea of value for money. Most claimed to be able to give us just what we wanted, made to measure, but we wanted standard designs at good value for money and low U values.

Many suppliers quoted low U values but it was difficult to tell whether the value quoted referred to the whole unit or the centre of the pane, which is misleading.

We picked up a lot of leaflets and felt the best approach was to get the spec for the windows we wanted and then send out for quotes. One of the windows in the Zero Carbon House looked interesting as it had a cork insulator between the frame and the pane to reach a U value of 1.3 for the unit.

We looked for staircase ideas but did not get far with these either. Returning home we put “staircase” into Google Images and found lots of interesting ideas. The one we liked best was the Universal Maxi Staircase exporting direct from Italy. We placed an enquiry on their web site. This morning I have found a UK supplier, The Wooden Hill Company Ltd in Dorking and a price of £1288 inc delivery and VAT. Not bad for our only WOW factor.

Zero Carbon House at EcoBuild

A bit chaotic as there was a huge queue to go upstairs but no one to see when upstairs was empty. The Titon HRV1 was worth a look. As a heat recovery system it could be compared with the Villavent and Vent Axia products. Vent Axia were very helpful on their stand and suggested that little expertise was needed for installation which could be a DIY job.

The most interesting feature was the LED lighting by Lamdyne in France. Strip lights appeared very bright and suitable for kitchen, office or bathroom use. All we could take away was a price list from France giving prices from E290 each! Even with 50,000 hours life and half the consumption of mini-fluorescents this was rather too expensive!

Non-Eco Travel 09/03/09

Betty went to Lanzarote to see the grandchildren for 9 days. She needed the break as she had become very discouraged by the delays and setbacks. Not very eco you may say. I agree, but I don’t believe in voluntary restraint because it will not be enough to remedy the situation.

As I believe personal carbon rationing will be necessary before we can reach even 50% cuts (let alone the much deeper cuts that are needed) our actions will be to demonstrate how this may be achieved in residential housing and to let others model other aspects of the solution.

Some Disappointments 10/03/09

We had not heard from Michael regarding the colleague but when I phoned last week he said he would be away for a couple of weeks so better to go ahead with the lady in Wales. He asked me to send copies of the plans to her. When I told my neighbour Kevin he offered to make sure that the information we were supplying would be sufficient for her to do the job well.

She would need a copy of the conditions from the Outline Planning acceptance. Looking at these again there was a condition that the extension and works would be in the existing materials (even though the application had said “possibly rendered”).

She would prefer CAD drawings but at least the dimensions would have to be clear and accurate. She would also need the structural calculations for specifying the steel beams. I copied the papers and Kevin came over in the evening.

He pointed out the need for drains for the new bathroom, en suite and relocated cloakroom. I wondered at what point these would be considered but there was some evidence on the drawings that Michael had thought about it.

Inspection revealed that the manhole by the front door served only the downstairs toilet and all other effluent left the back of the house to a manhole half way under the neighbour’s fence! According to a very old drawing our effluent then passes under next door garage and down to the road. This manhole is at the precise point at which the corner of the extension is planned to be.

The sink water could continue to use this outlet but the cloakroom in the middle of the house and the en suite directly above it would need a new route under house and garage where it would be joined by the new bathroom effluent in a new pipe to the road. This sounds rather expensive and outside our budget.

The solution for the rear manhole is probably to move the extension 2 feet away from the boundary (where I had unwittingly drawn it originally).

Bradstone Planning and Patterns 10/03/09

The discipline of turning outline plans into Building Plans got me thinking about another problem. The outline plans required some adjustment of window sizes and this might be difficult in our 1960’s version of Bradstone. The walls are made from 11 different Bradstone block sizes from 15 inch by 9 inch down to 4 inch by 3 inch. The height of the blocks is always a multiple of 3 inches. They are laid in a not repeating pattern so that they neatly fill the space to the next opening (door, window) or corner. The front door is bordered by 9 inch high smooth blocks alternately 9 inch and 4 and a half inches wide.

As a result, moving a door opening by 10 inches has its problems!

As a start all changes must be in imperial measure and must be multiples of 3 inches. Each change will be a mini jigsaw puzzle and we must rely on getting the blocks in the sizes necessary. It sounds rather expensive and risky to me! Perhaps we can minimize the changes, where they will be visible, on the next set of plans.

Michael Gregory has contacted the Cherwell Planning Department who have ruled that the approval was for the use of matching materials so no part of the extension could be rendered. The application was made for the walls to be constructed in the original materials, possibly rendered. This was really too ambiguous and allowed the planners to approve the application to build with the condition that original materials are to be used.

This is just the opposite of what we had hoped and makes it very difficult to achieve standards of insulation we would desire, particularly as the two extensions have 3 walls exposed to the elements. Where to from here?

Loft insulation problems 10/03/09

It is a wet and windy day so I went to do some more insulating in the loft. The Celotex and sealing is going quite well but as I sat admiring my work I noticed how much wind was coming from under the eaves into the loft. Unless I could make the loft airtight it could not form the basis for insulating the house. The eaves must be left windy but the rafter insulation must meet the ceiling in an airtight join. Getting in to that corner and doing any work is virtually impossible. What is the solution and how expensive?

It looks as though a spray insulation or render would be the best option but I will have to look into this. Perhaps Tradical Hemcrete would be suitable.

A better day 11/03/09

After getting the neighbour’s permission I cut a small panel out of the base of the fence to enable me lift the manhole cover between us. It was half full of earth and had not been used for many years. I ran our sink tap and there was definitely no water flowing there. I lifted the two traps in the neighbour’s front garden and the water had arrived there OK – but how? More exploration is needed.. Perhaps the foundations of the new kitchen may need to bridge a drain nearer the house.

I had further thoughts on the loft. It would be possible to put a block of Celotex between the floor joists so that the top bonded to the Celotex between the rafters and below to the ceiling board to make this fairly air tight to reduce the gusts hitting the foil layer. Then the Triso Super 10 foil could be cut round the floor joists and glued to the ceiling for the final draught seal.

Ice Energy Survey 11/03/09

I had prepared for the Ice Energy Survey by drawing a plan of the collector trenches and sending it to the office in advance. By doing this I thought I would get a more precise approval than just a verbal statement that the garden was suitable.

The surveyor was due at about noon but phoned at 2pm to say he had been delayed 7 hours on a job in Northampton and would be with me in about an hour. Josh, the surveyor, was a pleasant young guy with tattoos all the way up his arms and a cheery manner. He was surprised by my plan and said most customers did not even know the size of their gardens. He studied the plan, saw how it matched the garden, and could find no fault with it.

I asked him about a plan I had to replace the energy in the ground by laying a garden hose beside the slinky pipe and circulating water in the Summer to a small water feature. He approved.

He said colder soil temperatures would keep moles away and deter roots from attaching themselves to the pipes. I asked whether this would be in the Summer too.

He filled in a checklist of questions regarding house insulation and the method of entry for the pipework and he recommended a manhole for the manifolds outside the house and high performance Armaflex insulation (not supplied) for the pipes themselves as they enter the house.

He approved the place we proposed for the heat pump and storage tank but said there would not be room for an airing cupboard as the pipework on top of the heat pump would prevent it.

They would not want to be present while the slinky was being laid and would not return until the whole system was ready for commissioning. However they were available to answer any questions we might have.

Safestyle UK 12/03/09

I saw these windows in the Zero Carbon House at the Eco-Build Exhibition. The web site was not very informative so I filled in their form and they contacted me. They were keen for someone to call to discuss our project so we made an appointment for today.

Harry, the representative, was on the dot of 12 noon as planned but when he knew that our windows were likely to change before the final version he felt he had come too soon for our purposes.

The main reason for the call was to get some idea of price for the budget but he was reluctant to give a price for a typical window. All he would say was that if we ordered 11 windows from SafeStyle they would work our about £500 per window. They would be their Diamond Standard window and he showed me a sample. They would be glazed with Pilkington argon filled double glazing which allows the solar radiation to enter and reflect the room heat (infrared radiation) back into the room. The window could be opened so that the glass could easily be cleaned on both sides. It would be possible to reach the adjacent window too, with difficulty.

He said they were the largest suppliers of windows in the UK, larger than either Anglian (our present windows) or Everest who are better known for their advertising. He assured me that their windows were of the highest quality and that our Anglian windows should not be letting in draughts after just 15 years.

Inside the PVC frame there was a steel frame to give rigidity and to enable the locks to engage securely. I asked about the U value of this window. He looked through his literature but he could not tell me.

This was when he mentioned the window we saw at the exhibition. It was their new Eco Window but would cost approximately £2700 per window. Not in our budget I’m afraid.

He was also reluctant to give me a price for the front door. When pressed with the scenario that I was buying 11 windows from him he said the door would be between £700 and £1000.

He was interested in our project and I was impressed with the way he presented his company and his cautious friendly attitude.

I decided to cheer my wife up with a surprise on her return as she has been very disappointed with all the mistakes and delays. I have started to strip the last of the old wallpapers off the staircase. We had left this knowing the stairs would be moved but I think it will encourage her.

Homebuilding and Renovating Show 21/03/09

The best show yet! Although not billed as an eco-show this show at the NEC was more helpful than any we had attended before. The show was less crowded and exhibitors had time to explain their products and discuss our project.

We attended free seminars on Ground Source Heating and on Managing a Project to Time and to Budget. Both were good and confirmed our work so far while giving us more valuable information.

I had two objectives, to improve my understanding of underfloor heating, and to get the best cavity wall insulation available. Betty wanted to check doors, windows and staircases.

I was impressed with several of the stands. Chelmer Heating were good. They showed a Retromat product in which fine pipework is rolled out secured in a copper wire mesh. It is designed for operation at 30 degrees and has 9mm Phonotherm insulation underneath and 15mm screed on top to total only 24mm! Including the pipework and mixing valves they said the system should work out at about £50 per sq metre installed. This may still be our best option.

Enersys had an excellent display and helpful staff but did not seem to come down to our budget.

I am not sure we can afford full installation and rather hope for a product we can install ourselves. This looked possible on the Boulder Developments Stand where they gave samples of Superfoil insulation. The SFUF product was shown with underfloor heating pipe attached directly to the floor through it. This would be only 6mm depth plus the pipes (12mm) and clips. However they suggest screed on top to the pipe manufacturer’s instructions.

Polypipe were next and they provide pipe and a design service which may go with the Superfoil. Their own Overlay system looks good too but I have not been able to find out how thick this works out yet.

The existing materials condition 05/04/09

Much of the past month has been dominated by the ‘existing materials’ condition which was condition no 2 of our planning consent. The first step was to try to obtain matching materials. I tried the 20 or so members of, the association of reclaimed materials, and none of them could help. I then started phoning the 30 or so demolition companies and most of them crushed or sold the materials they obtained.

It looked as though a change to render would be inevitable so I took photos of the blends of Bradstone and render in our road, to establish precedent, and also a picture of an extension in new Bradstone on an older Bradstone house to show the rather poor result.

On the internet we had found Winchcombe Reclamation in 2007 who said they stocked recycled Bradstone so we made an appointment to see what they had. A day in Gloucester was pleasant but they did not have anything to blend with or match our Bradstone blocks.

I sent the photos and an email of my impression of the result to Mr Ihringer at Cherwell Planning. He replied once again that a change to render would need a new planning application.

To keep our neighbour informed we invited her for a drink. She said she thought render might be OK. We asked whether she would be prepared to write a letter to that effect and she said she would need to have a look at the examples in the village, but would consider it.

Back to square one with all the doubts and delays again!

Then Betty woke up with a thought! Surrounding the front door, on the chimneys and between the garages the openings are framed with a smoother style of Bradstone and it might be easier to match that.

An internet search confirmed this ad we contacted local Bradstone agents to get samples.

While we were about it we will look at samples of the tiles as well which appear to be Sandtoft Stonewold 2. So we are off to TK Timms at Brize Norton in the morning.

Well not so good really 06/04/09

Timms were very helpful, taking us round the yard and showing us their stock. The Bradstone Blocks were once again too yellow and the fairfaced (which just means smooth) blocks were too coarse except for some which appeared to match our quoins quite well. These priced at £15 per block and would cost £7200 in total!

Back to the drawing board! It had become clear that no Bradstone agent holds the full range of Bradstone samples

If we are going to make a new application for planning we want to be quite sure existing Bradstone Square Dressed or similar stone is not suitable so we need to see the full range. A call to the Bradstone sales office established their opening hours and they agreed to have a sample of their fairfaced block in the office for examination. We drove through the front gates of Aggregate Industries in Swindon and found ourselves in a bewildering yard full of huge vehicles, piles in stock, notices everywhere and small anonymous offices dotted about. We looked in an office which said Bradstone outside and they thought we should ask at reception. Where was reception? Betty asked in another works doorway and was directed back and around the perimeter road to the Bradstone department which must have been a quarter of a mile away!

Once there they were so helpful. The fairfaced block was still very coarse and difficult to use for a good finish. The colour we had chosen could only be a special order of 150 square metres and we only wanted 30! A smoother stone was available but they did not have a suitable colour. However the Square Dressed block came not only in the buff, which was too yellow for us, but also in Pennine which is a grey and buff colour which could blend well. At last a little light at the end of the tunnel. They advised we get the local agent to give us a price as it should be better than buying direct from them.

A choice of Windows 09/04/09

Betty wanted to talk to another window company and had the name Everest on her mind. She booked a visit for a quote and a smart and charming young man arrived in an Alpha Romeo. He showed us designs, talked through our needs and emphasised that his company’s ‘Fit the Best’ logo had been approved by the independent window evaluation body. We went round the house together listing and measuring the windows which will remain and the sizes of the new ones. We talked front doors and garage doors. We heard how their windows were uniquely strong and long lasting for 3 and a half hours and then he paused to work out the price of 15 windows, a front and a back door and a garage door. We held our breath!

After about 10 minutes he called us back to say £53,245 and that would include removal and disposal of all the old units!

More than the house we said!

Ah! He said. We can allow 30% discount because you are ordering in the Winter and it keeps the factory working. After a short pause there was a further 10% for quantity discount and another 10% rebate of hire purchase commission, 10% for immediate order discount and a further 10% plus a free garage door opener because I am over 65! This brought us briefly down to a total of £20,800 or so but as this included the immediate order discount he could not leave this with us if we did not order today. It would not be fair he said.

“Had we had any other quotes?” he asked. When I mentioned the £5500 for 11 windows from Safesure he said that at that price the product would be inferior.

As he eventually reversed out of our drive in his Alpha I wondered who paid for it.

Our search continued with Wickes windows and B&Q windows in the region of £200-300 each but they were more limited in their range of sizes which would mean new windows could be theirs but other windows would have to be made to measure to match. Safestyle looks the best so far.

Kitchen worktops

In B&Q we found the completely moulded kitchen sink and worktop that we admire. It is a stone like covering for a chipboard top which means easy cleaning and a smooth touch even where the sink joins the worktop. A rough price guide for the 2 metre worktop we saw was £1500 so our tops would be about £3000. Should this be our special feature, or are we already over budget?

Must start something! 23/03/09

Still no plans to enable us to get quotes so perhaps we can start on the ground source ground works and get them out of the way before the builders start. We placed the order for the pipework as it may have a 6 weeks delivery but they plan to deliver it in one week's time. Wow!

Will make a note to order the sand and the digger soon after it arrives and meanwhile will get the other bits required like the special insulation

Rain stopped Play 08/04/09 – then success

Had planned the digger for today but had to put it off because of the forecast of rain. About an inch of rain over 4 days might make the operation a bit dangerous.

A false alarm! Wonderful weather! I have slipped another week. Next week rain is forecast too but I will go ahead anyway.

The groundworks project went very well and was great fun. It took much longer than expected and full details are available in a separate booklet at the end which I recommend for anyone planning a similar job themselves.

Plans at last! 11/05/09

Well Easter intervened, and Jeanette was not well, then all went quiet so we started the ground source work. Then, 3 days before our holiday in Canada the first draft of the building plans arrived by email.

I could only print A4 sheets so had to manipulate the pdf sheet to print a part at a time. Jeanette had done a great job resolving most of the small differences between my working plans and those submitted for approval by Michael. Only one problem appeared to us to be serious. In our attempt to gather the rainwater from the garage without spilling onto the neighbour's garage roof I had proposed a gutter inside the garage on our side of the party wall. When drafted up this had lowered the garage roof on that side and thrown out all the symmetry which made the front roofs so attractive.

s you can see the roof over the garage is not centred over the garage door, the roof lines are truncated at the porch and the dining pitch is flatter than the main roof pitch. It does not seem wise to leave this to be sorted out by the builders.

However the changes necessary will not affect the cost, so after discussion with one of our proposed builders we decided to send them the existing set of drawings so that they could prepare a quotation while we are in Canada for 3 weeks holiday.

Quotation Requests 12/05/09

We telephoned 3 builders recommended by our architect Michael to ask them if they wished to quote for the work. 2 have not yet replied and one was very keen to quote so we thought we would try to get 2 quotations rather than put others to unnecessary trouble.

It will not be an easy job as I may need to do some of the work myself to keep the cost down. We also want to remain in residence for as long as possible to reduce rental costs. I produced the following document to help with the planning. We also enclosed the 2 drawings on A3 paper provided by Jeanette and plans of the existing building as requested.

Marchwood Eco-Renovation

Quotation is requested for the following items individually.

Occupation of kitchen, lounge,bedrooms and bathroom to be maintained through 1 and 2.

DIY fitting of underfloor heating pipes in 1st bedroom during 1 and 2.

  1. Build kitchen/breakfast room extension to rear in Bradstone Square Dressed Pennine in the recommended mixture 40% 3 inch, 40% 6 inch and 20% 9 inch similar to existing appearance including new double glazed E glass UPVC windows and roof lights. Tiles to be Redland Stonewold 2 to match existing roof. Walls constructed to 0.17 U value specification recommended by Bradstone 100mm Masterblock Masterlight Xtra, 100mm Rockwool blown, 22mm Insulating Thermal Plasterboard. Floor level to match existing kitchen as both to have 40mm underfloor heating plus ceramic tiles. Incorporate underfloor heating pipes and cut path for ground source pipes into kitchen. Include electrics. No further heating or plumbing.

  2. Build 4th Bedroom Extension to similar specification. To include roofing over garage and lounge. Internal work necessary to fit and support steelwork. Remove 1st bed window to increase front wall to allow completion of 4th bed wall. Cover space. Include roof lights but fit only for lantern light. Include underfloor heating pipes between joists and electrics.

  3. Remove kitchen chimney from kitchen and above. Remove cloakroom walls and upstairs to permit new staircase. Resize new bathroom window aperture.

  4. Extend extractor piping to gather from utility room dryer. Incorporate Villavent pipes in ceilings and wet areas as planned. Move internal walls upstairs to build en-suite, bathroom and 2 bedrooms and fit and plumb services, electrics and drainage while leaving old bathroom and 1st bedroom functioning. Query heating pipes in new partitions or under floor. Then close doorway to garage, fit new staircase, remove old and make good flooring. Complete fitting bathroom, en-suite and cloakroom cutting new drainage to street manhole. Plumb and drain to utility sink and dryer extractor. Make new door from utility to garage

  5. Connect ventilation system as planned by Villavent

  6. Remove existing ground floor covering, lay Superfoil SFUF underfloor insulation on existing ground floor, clip pipework to floor, lay Knauf Brio 23mm screed boards onto pipework and tile throughout. Labour cost only. Also provide tile only cost please.

  7. Complete plumbing for Heat pump

  8. Decorate throughout

Returning from Holiday 06/06/09

We have returned from 3 weeks with Betty’s brother in Canada. We had asked Michael and Jeanette to solve the remaining problems in the drawings while we were away but Michael emailed to say Jeanette had not been in touch. I asked him to get in touch with her and meanwhile I examined my dimensioned Sketchup model to see what had to be adjusted to make the roof gables look symmetrical. It did not seem too difficult but I do not have the CAD software she uses so am not sure what the problem was.

As we went on holiday we left a request with Fran, next door, for permission to work on the party wall of her garage. She has left us a note saying she is concerned that her electrics on the wall may get wet and that any plans she hs in future to build on the party wall may be jeopardised. Now she is away and asks if we can discuss the matter when she returns with full drawings of the work to be done.

We met one of the builders at the local Otmoor Challenge and he said he had a few small questions to complete his quote. I tried unsuccessfully to phone the other builder to see how things were going but will have to try again on Monday.

AECB Annual Conference 11/06/09

The first evening of the Sustainable Building Association Annual Conference was open to the public and consisted of 3 eco-renovators sharing their experiences and answering questions. It was in Oxford Brookes Main Lecture Hall and about 250 people attended. Although we were too far down the line for major changes we were looking to pick up a few pointers.

The first was on the TeploTie stand in the foyer exhibition where we collected a sample of a mineral wall tie which claimed 10 to 40% reduction in the bridging heat losses. It seems such an obvious improvement.

The renovators and the questions asked by the audience quite overawed us. However their problems focussed on Victorian houses with solid walls which needed very different treatment than ours. The dangers of condensation within the insulation forced some difficult choices. We were pleased that we had tackled this danger by installing a ventilation and heat recovery system that would detect and extract damp air before problems arose.

All the renovators were highly qualified with their masters degrees in this and that and were motivated in many cases by a need to prove they could achieve a good result in a particular kind of property. It became clear that a good result was to be judged in terms of their individual philosophy of desirable achievement which they explained.

They had their targets for reduction of CO2 emissions in operation, reduction of CO2 emissions in construction, energy reduction, use of sustainable materials, reuse of materials, water saving, as well as their own curiosities like green roofs.

For example one property was heated by a wood burning stove using waste wood and so claimed to be totally sustainable. They dismissed ground source heating as too expensive and carbon intensive because it used electricity generated largely from coal and gas.

While I respect this point of view, it appears to be a local and short term one. There is not enough waste wood to enable a large section of the population of UK or the world to follow this example. Looking at the daunting task of 50% or greater cut in CO2 emissions it would appear impossible unless all electricity is generated from renewables, preferably without any combustion. Then ground source comes into its own, and costs can be reduced to an affordable level by volume manufacture. After all a £10,000 compulsory loan to install ground source heating in every possible house would not be impossible. We have just taken on a similar debt as a result of the banks’ failure.

We were encouraged that our philosophy might soon be in vogue!

Another learning point was that 2 out of 3 owners had vacated their properties while the work was being done and the third had most of the work done on the outside. We must make sure that we have an escape route if it gets too difficult to live on a building site.

Discussing the Quotation 13/06/09

This morning our preferred builder came round to ask a few questions. We got on well as he seemed to have the same concerns about the architect’s drawings as we had. He had declined to quote 2 other extensions as he likes to do one at a time so we really hope we can afford his quotation.

His questions related to the shape of Velux windows, whether we wanted to replace windows in the bathroom and landing, how the long sloping roof would be supported. He warned that it would not be easy to live in the property while the extensions were being built as there would be some work on the old part too. We showed him our plan for the phased removal and storage of our belongings and agreed to give it a try anyway.

He asked whether the oil tank was to be used for water and we discussed when it would be best to dig the hole without coming to any conclusion. If we dig the hole when the ground works are being done we would have to empty the oil tank in the next couple of weeks. We can have it professionally done but if we do it ourselves we would have to take 100 litres of oil round to our daughter 5 miles away. We need containers. A look on Ebay revealed a pack of 5 x 5 litre containers for £4.95 at Camberley 30 miles away. 2 packs would mean we could transport all the oil in 2 journeys.

Temporary Accommodation 14/06/09

We want to move out about October, after the extensions are built, at the latest to let the builders renovate the older part of the premises. We looked at renting but this starts at £625 per month for a 1 bed and might not be very flexible if the work overruns the schedule. We thought of a motor home but anything we could afford would be too cramped for static living and cost on tax, insurance and depreciation. We have been looking at various caravans for a while now as they depreciate very little and we have a local site at Commonleys Farm which provides electric hookup for £70 per week occupied or £50 per week stored. We also have a neighbour who is willing to store the van a bit nearer until we need it.

We only have a small 9 year old Skoda Felicia so would need a very light caravan if we wanted to tow it. We decided this kind of van would not be big enough to be comfortable in the Winter, so have been looking for something more roomy. Our daughter has agreed to collect it for us with her Range Rover so we will not need a tow bar either.

4 to 5 berth vans on Ebay seem to go for around £1500 but they are most up North. The local Freeads showed an Avondale Pearl in Abingdon for £1000 so we went to see it.

It was very clean inside, which was our major consideration, and came very well equipped with everything we seemed to need. The couple seemed pleasant and, though they were smokers, the van did not smell at all of smoke. It did not have the separate double bed at one end that we were hoping for but we thought it was a real possibility so we went for it. We left a deposit and agreed to pay the balance on collection next weekend by arrangement. Wow! We had bought the first caravan we really looked at!

Back at home we saw 7 Avondale Caravans of similar age on Ebay starting at £500 or so. Have we paid too much? We will watch to see how they end – but there is nothing we can do about it now anyway.

Appendix 1

1.Typical R-values thickness

All values are approximations, based on the average of available results.

2.List of examples

Values per inch. The R-values are given in imperial units (ft²·°F·h/Btu).; the numbers in parentheses are their SI equivalents.


Value per inch (Min)  

Value per inch (Max)  


Still Air

R-5 (0.88)

Still Air with convective currents

R-1 (0.18) (or less)

R-5 (0.88) (Still)

Wood chips and other loose-fill wood products

R-1 (0.18)


R-1 (0.18)

Straw bale

R-1.45 (0.26)


Wood panels, such as sheathing

R-2.5 (0.44)

Vermiculite loose-fill

R-2.13 (0.38)

R-2.4 (0.42)

Perlite loose-fill

R-2.7 (0.48)

Rock and slag wool loose-fill

R-2.5 (0.44)

R-3.7 (0.65)


Rock and slag wool batts

R-3 (0.52)

R-3.85 (0.68)

Fiberglass loose-fill

R-2.5 (0.44)

R-3.7 (0.65)


Fiberglass rigid panel

R-2.5 (0.44)

Fiberglass batts

R-3.1 (0.55)

R-4.3 (0.76)

High-density fiberglass batts

R-3.6 (0.63)

R-5 (0.88)

Cementitious foam

R-2 (0.35)

R-3.9 (0.69)

Cellulose loose-fill

R-3 (0.52)

R-3.8 (0.67)


Cellulose wet-spray

R-3 (0.52)

R-3.8 (0.67)


Cotton batts (Blue Jean Insulation)

R-3.7 (0.65)


Icynene spray

R-3.6 (0.63)


Icynene loose-fill (pour fill)

R-4 (0.70)


Urea-formaldehyde foam

R-4 (0.70)

R-4.6 (0.81)

Urea-formaldehyde panels

R-5 (0.88)

R-6 (1.06)

Polyethylene foam

R-3 (0.52)

Phenolic spray foam

R-4.8 (0.85)

R-7 (1.23)

Phenolic rigid panel

R-4 (0.70)

R-5 (0.88)

Molded expanded polystyrene (EPS) low-density

R-3.7 (0.65)

Molded expanded polystyrene (EPS) high-density

R-4 (0.70)

Extruded expanded polystyrene (XPS) low-density

R-3.6 (0.63)

R-4.7 (0.82)

Extruded expanded polystyrene (XPS) high-density

R-5 (0.88)

R-5.4 (0.95)

Open-cell polyurethane spray foam

R-3.6 (0.63)

Closed-cell polyurethane spray foam

R-5.5 (0.97)

R-6.5 (1.14)

Polyurethane rigid panel (Pentane expanded) initial

R-6.8 (1.20)

Polyurethane rigid panel (Pentane expanded) aged 5-10 years

R-5.5 (0.97)

Polyurethane rigid panel (CFC/HCFC expanded) initial

R-7 (1.23)

R-8 (1.41)

Polyurethane rigid panel (CFC/HCFC expanded) aged 5-10 years

R-6.25 (1.10)

Polyisocyanurate spray foam

R-4.3 (0.76)

R-8.3 (1.46)

Foil-faced polyisocyanurate rigid panel (Pentane expanded ) initial

R-6.8 (1.20)

Foil-faced polyisocyanurate rigid panel (Pentane expanded) aged 5-10 years

R-5.5 (0.97)

Silica aerogel

R-10 (1.76)

Vacuum insulated panel

R-30 (5.28)

R-50 (8.80)


R-3 (0.52)

R-4 (0.70)

Thinsulate clothing insulation

R-5.75 (1.01)

Values for a specified unit (not per inch)


Value not per inch (Min)  

Value not per inch (Max)  


Reflective insulation


R-14 (dubious claim for a specific complete assembly)

[8] [12]

Single pane glass window

R-1 (0.18)

Double pane glass window

R-2 (0.35)

Double pane glass window with low emissivity coating

R-3 (0.52)

Triple pane glass window

R-3 (0.52)

Materials such as natural rock, dirt, sod, adobe, and concrete have poor thermal resistance (R-value typically less than R-1 (0.17)), but work well for thermal mass applications because of their high specific heat.

3.U.S. regulation

The Federal Trade Commission (FTC) governs claims about R-values to protect consumers against deceptive and misleading advertising claims. "The Commission issued the R-Value Rule[13] to prohibit, on an industry-wide basis, specific unfair or deceptive acts or practices." (70 Fed. Reg. at 31,259 (May 31, 2005).)

The primary purpose of the Rule, therefore, is to correct the failure of the home insulation marketplace to provide this essential pre-purchase information to the consumer. The information will give consumers an opportunity to compare relative insulating efficiencies, to select the product with the greatest efficiency and potential for energy savings, to make a cost-effective purchase and to consider the main variables limiting insulation effectiveness and realization of claimed energy savings.

The Rule mandates that specific R-value information for home insulation products be disclosed in certain ads and at the point of sale. The purpose of the R-value disclosure requirement for advertising is to prevent consumers from being misled by certain claims which have a bearing on insulating value. At the point of transaction, some consumers will be able to get the requisite R-value information from the label on the insulation package. However, since the evidence shows that packages are often unavailable for inspection prior to purchase, no labeled information would be available to consumers in many instances. As a result, the Rule requires that a fact sheet be available to consumers for inspection before they make their purchase.

      1. Party Walls - Adjoining Owner's rights

What is a Party Wall?

A Party Wall is a wall shared by two (or more) properties which is usually divided by the boundary line but can include a wall, solely on one property, where an adjoining building derives support from it. It could also include a freestanding garden wall if it is built astride the boundary.  Fences are not included in this definition.

What are my rights?

The building owner is legally obliged to give you Notice and details of the proposed works which, structurally affect the Party Wall or of any excavations close to the Wall.  If you do not respond to a Notice within 14 days a dispute is deemed to have arisen.

What if I am not happy with their proposal?

You are advised to let the adjoining owner know as soon as possible and to appoint your own surveyor, if necessary, to check out the proposals and safeguard your own interests.

Should I appoint my own Surveyor?

If you cannot decide on an "agreed surveyor" acting for both you and your neighbour, for whatever reason and if after discussing the proposals with your neighbour you are not satisfied or you still have concerns you should choose a qualified person experienced in dealing with Party Wall matters. An Institution such as the RICS* will supply you with a list of local surveyors. (Surveyors engaged for the purposes of the Act should act on an impartial basis).

Who pays?

The building owner carrying out the work is expected to pay all reasonable costs.

What is the Council's role in this?

Where these works involve an application, the Building Control Section will carry out inspections to ensure the work is structurally sound and complies with the Building Regulations but cannot act on your behalf regarding this legislation.

What about access to my land by my neighbour?

Under the Act, you must allow your neighbours workmen and surveyors access to your land in so far as it relates to work in connection with the Party Wall. However, the adjoining owner must give you 14 days notice of their intention to exercise these rights of entry if agreement hasn't already been reached.

What if I refuse entry?

It is an offence, which can be prosecuted in the Magistrates Court, to refuse entry or obstruct someone who is entitled to enter premises under the Act.

Legal Note

This information is not an authoritative interpretation of the law and no substitute for the Act itself.

Reaching agreement with your neighbour under the Act does not remove the possible need for Planning Permission or Building Regulation approval.

RICS - Royal Institution of Chartered Surveyors is located at 12 Great George Street, Parliament Square, SW1P 3AD
Telephone:  020 7222 7000