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Large Victorian Semi-detached House

This was not a major renovation, but rather a gradual energy efficiency upgrade which so far has reduced our CO2 emissions by 75%. Our house, in Walsall in the West Midlands, was constructed in 1903. Like nearly all houses built before 1928 it has solid brick walls which have negligible insulation value. We moved in when our two children were still in primary school, in 1983. The house was in fairly good condition, in need only of minor damp work and redecoration. It was heated by electric storage heaters, and had no insulation, so we immediately insulated the loft and the hot water tank and draughtstripped the house, and installed a weather sensor control for the storage heaters.

Then it was all quiet on the energy front until 1999, by which time our two children had flown the nest. We started by replacing the storage heaters with a carefully specified central heating system which turned out to comply with the 2005 Building regulations.  The result exceeded expectation as we cut our CO2 emissions by 60% at a stroke. Note that replacing an old boiler (the type with a pilot light) can achieve similar emissions reductions if you also upgrade controls and insulate pipes.

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Then over a period of years we have drastically improved the wall insulation one room at a time, when doing other work such as decoration or new kitchen, or just when we felt sufficiently energetic. We have also largely double glazed, without altering the appearance at the front.

Thus we believe our approach demonstrates how very substantial emissions reductions can be achieved on a limited budget by making changes in instalments and by using DIY and a one man builder. If you are lucky enough to have cavity walls, then just have them insulated professionally, and go down to the pub while we are sweating away insulating solid walls. 

When our emissions reduction hit 70% we named the house "Walsall Ecohouse". Currently our CO2 emissions are 75% below their 1998 level. We have no renewables, as the payback times are even longer than for the internal wall insulation. However we are planning a modest active solar air heating system which will collect warm air in a blind window (to be set against the wall upstairs at the south facing rear) and fan it through pipes to the North facing front room. (Web search "active solar air”).

Vital Statistics

This property was built between 1700-1920. It is a semi-detached house with 5 bedrooms, located in a suburban area in West Midlands The household is a semi-retired couple, with an average occupancy of 2 all year round. No planning restrictions are in effect.

Annual Energy Use

Electricity: 2,200.00 kWh (Standard)

Gas: 909.00 cubic metres

About us and why we did it

We are Martin and Jane Normanton.

We've always disliked waste and planet abuse, and Martin has had a long interest in energy efficiency. It was a growing concern about climate change, and a trip to the Hockerton Housing Project, that motivated us in 1999 to start to go far beyond the easy measures of loft and cylinder insulation.

Have a look at Hockerton Housing Project for a view of what the Hockerton Housing Project is all about.

If having read about our eco renovations you would like to contact us, please do so at

Visits to our house are also available by appointment. (Walsall is between Birmingham and Wolverhampton).

Heating and Power

Through the installation of TRVs, a new condensing combi boiler and acute attention to detail, in terms of when and how we use our heating, our energy consumption has diminished significantly.

In 1999 we replaced the storage heaters with gas central heating powered by a Worcester Bosch Greenstar HE 30 condensing combi boiler. We employed a plumber we knew and trusted to install the boiler and oversized radiators downstairs, and insulation of all pipes running in unheated areas. We specified the best controls, i.e. a programmable room [house] thermostat as well plus Thermostatic Radiator Valves (TRVs). If we were doing the work now we would certainly upgrade to the HE Plus version of the boiler, which works with an intelligent room thermostat to modulate the boiler down as the desired room temperature is approached.

Hot water for our shower and bath are provided by the combi boiler. Hot water for the kitchen and bathroom sinks is provided by individual electric water heaters with 10 litre storage tanks. The small quantities of water used in the sinks are not an efficient use of the boiler and much of the heat is lost in the pipe run - not to mention the time wasted waiting for it to arrive. Although they are not as well insulated as we would like, the tanks are set to hand hot and so heat losses are bearable. 

Originally we did not think it would be truly cost effective to replace storage heaters that still worked. However the fuel savings far exceeded our expectations and the project was on course for a ten year payback when rising fuel prices shortened this to seven years! Note that an old gas heating system with a boiler with a pilot light and poor controls is just as bad as storage heaters for CO2 emissions.

To minimise gas use Martin does “the dance of the TRVs” (thermostatic radiator valves) which aims to heat different rooms at different times. The dance goes as follows: When going to bed turn down the TRVs in the living room and study and turn up the TRV in the kitchen-diner and bathroom, so that when the programmable thermostat brings the heat on in the morning only the necessary rooms will warm up. Then at breakfast time turn up the living room and study TRVs and turn the kitchen-diner and bathroom ones part way down. If we are going out for long we turn the programmable thermostat down one degree.


We focused extensively on insulation, applying different methods to the different environments throughout our house. The insulation of the solid walls has been a major project and we have achieved it in instalments, as opportunities arose. 

Most of the insulation is internal wall insulation (IWI). This has the advantage, compared to external insulation, of relative cheapness. If you are renovating a wreck the extra cost is minimal, but in our case the plaster was sound, so it has been an expensive project; the cost including labour is in the region of £500 per room, giving 20 year payback. Replacing the Victorian plaster coving in the Dining Room the cost a further £600! Currently we have just insulated the front living room, and have ordered replacement coving in wood at a third the cost; we just hope we will be able to install it OK! The insulation should raise the value of the house since Home Energy Surveys will be required for all house sales after June 2007. And of course properly installed insulation needs no maintenance.

The system we have used is Martin's invention, honed over successive rooms. 

The common method is to use insulated plasterboard which is now available with fairly good insulation levels, but a problem remains in ensuring a good seal for the vapour barrier. The boards need to be installed with the full perimeter bead of adhesive on each one to prevent moist air from getting behind them and forming condensation. Even with care you cannot be sure that each bead has made full contact with uneven walls - assuming that your builder is willing to apply a full bead in the first place.

So instead we have developed a system where we can SEE that the vapour barrier is complete before finishing off with ordinary plasterboard:

Polyurethane foam insulation sheets are placed against the wall and then held by 20mm battens secured by frame fixings passing through the insulation into the wall. The battens cannot rot as they are on the warm side of the insulation, so I call this a warm batten system. The insulation boards are foil backed both sides so the inner foil layer forms a vapour barrier, it “only” remains to prevent air from getting through the joints. The standard way of doing this is to use aluminium tape, but, while it sticks very well to the boards, having used it I have little confidence in its long term adhesion to the floor, ceiling and walls.

So we now use expanding foam to seal all the joints; to do this we leave 15mm gaps all around so that we can insert the tube of the can of expanding foam right into the gap. Only when I can see that the insulation is completely airtight does the plasterboard go on, hiding the unsightly mess behind.

The photo below shows the insulation in position  into the bay window on the right, and the first sheet of plasterboard has been positioned over it on the left. You can see the green expanding foam. In this room we wanted to minimise the thickness of the insulation system, so as well as hacking off the plaster we omitted the battens, holding the whole to the wall by frame fixings through the plasterboard.

While it achieved the aim, I would recommend using battens when you have space, as you can subsequently attach things (such as kitchen units) by screwing through into the battens, the gap created by the battens is useful for running services and if the wall is uneven you can correct this by packing the battens. When we insulated the wall in the kitchen, which has a solid floor, we also excavated a 100mm wide trench at the edge of the floor and insulated between the edge of the floor and the wall to a depth of 600mm. This works well as floor insulation while avoiding the expense of replacing the floor to insulate under it.

In 2002 we insulated the gable end wall where it is inside the garage (a full depth lean-to in brick) by an entirely different method which saves both cost and disruption. This is a form of external wall insulation, as it is applied in the garage, but being under cover it does not need to be weather proof nor professionally finished, so it is cheap and also lends itself to DIY. Because the insulation is fitted on the outside of the wall it avoids condensation by using the house wall as the vapour barrier (as in cavity wall insulation). It also avoids cold bridging at internal walls, not to mention the saving in cost and disruption by being in the garage and not inside the house. We used 200mm of fibreglass insulation on timber studs, covered by panelling consisting of a neighbour's discarded hardboard doors.

This still leaves one downstairs wall waiting to be insulated - the rear-facing study.

Pic: Solid Wall


Most lighting is by low energy bulbs.

With low energy bulbs 3W is enough for the hall light which is on all day. Almost as important as the efficiency of the bulb is how effectively the light is distributed to where it is required. Pendant lights are better than ones attached directly to the ceiling, and we use mostly uplighter or paper globe shades. Bathroom and bedroom lights which are rarely on for any length of time use 40 watt bulbs, and we last bought a 100 watt bulb in 1987. 


We begun with S Day (switch-off/ standby day), and from there culled, improved and replaced many of our electrical appliances, particularly those with stand-by options.

Standbys: S Day was 17th August 2001. That was when Martin switched everything “off” and timed the rotations per minute of the disc on the electricity meter. Calculations then showed that we were still using 86 watts. As there are 8,760 hours in a year that is an annual use of 753 KWh or 34% of our current consumption! War was declared and after the TV had been switched off at the switch, and the computers and VCRs at the sockets this figure was halved.

But where was the rest of it going? How about three LED clock-radios and two answer-phones? But how much were they using? Reinforcements were ordered in the form of a plug-in meter to measure the electricity consumption of individual appliances. The current one cost £25 from Maplins Electronics. This has revealed various horrors, and is accordingly named “The Judge”.

The Judge found that Jane’s halogen desk lamp used 4 watts when “off” – it is now awaiting recycling. The LED clock which is in our son’s bedroom was still on despite his having left 5 years before; it was unplugged, saving 3 watts. But not much we can do about the answer-phones which use 7 watts and 5 watts respectively.

The 22 year old fridge-freezer was also quickly condemned, but won a reprieve when we could not find a modern replacement with a big enough freezer. After being externally insulated with 60mm of polyurethane it is now about a ‘C’ rating. 

We found that our dishwasher used 1.5KWh per wash, so it has been replaced by Martin hand washing using about 0.2KWh for HW. The washing machine is an ‘A’ rated Bosch. The tumble drier was last used in 2004 and sparrows now nest in its vent.

Bathrooms and Toilets

We now have a Swedish Ifö Cera toilet, see The Green Building Store.

This uses only 2.5 to 4.5 litres of water per flush (the most used smaller flush is 60% less than conventional British models).

© Climate Outreach Information Network, 2006-2007
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