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The house, located in the Cambridgeshire town of March, 20 miles east of Peterborough, has already won the accolade of being the most energy efficient ever built in the Fenland District.  Tommy Walsh, who wants it to act as a "blueprint for affordable energy efficient housing of the future.", funded the project himself to show that you can build environmentally on a budget.

So what makes the house so fantastic?  It is packed full of high tech, energy saving, solutions that can be applied to any house given some for-thought, and they include:

Insulation
300mm of rockwool insulation was used in the loft. Rockwool is an inorganic stone wool insulation made from lava deposits of volcanic rocks which are melted in a cupola furnace like a controlled man-made volcano. As the re-melted lava comes out of the furnace, it is spun, given water repellency treatment and bound together in a wool-like fleece.



Heating
The house is heated by using an air source heat pump.  An air source heat pump is a heat pump that generally uses the outside air as a heat source. It works in much the same way as a fridge, but in reverse.  It has a coil with a refrigerant that has a boiling point of about -40°C, this means that it can generate heat even if the outside temperature gets as low as -15°C.

The refrigerant gas passes into a compressor which adds more heat energy and raises the temperature to around 75°C. This then passes into the condensing heat exchanger and as the refrigerant cools and condenses it passes heat energy into the water which is used to heat the radiators or underfloor heating pipes in the house.  Typically the heat passed into the house will be 3 to 4 times the energy used by the compressor and fan, so most of the heat supplied is renewable.

The air source heat pump isn't the best kind of heat pump; the geothermal heat pump is better because it makes use of a year-round constant underground temperature.  However, the air source heat pump is much cheaper to install because you don't need to dig up the garden to install it.

Electricity
The house has 16 Photovoltaic Solar Panels in the roof with a power output of 1kW.  Tommy used a solar panel design that fits into the roof along with the tiles. The design, which is much cheaper than solar systems that sits on top of the roof tiles, uses a special toughened glass.  Because the tiles fit flush into the roof, planning permission is not required.

Green Frog, the company that supplied the tiles say that a typical 3-4 bedroom house would require 8m² of Green Frog's Glass Solar Slates to provide sufficient heating, at a cost of £1,600 for materials.

Tommy explained his reason for using these tiles:
"Like many other people, I couldn't get a government grant for installing solar panels on my Eco House. It is a widespread problem. Fitting Green Frog Solar via a NICEIC approved electrician overcame the dilemma, allowing us to install solar quicker and more cost-effectively than going through the government grant process. Green Frog Solar, when used with Nu-lok's innovative roofing system, is a wonderful solution, enabling builders to install solar seamlessly – and the end result looks fantastic!"

Windows
The Windows were made of argon filled solar glass units, then glazed with Guardian energy efficient glass.  The problem with windows is that they let heat in and let heat out.  Putting argon in the gap between the window panes helps to insulate the inside temperature from the outside temperature.  But the windows that were fitted in this house also stop the house over-heating because of the sun.

Recycling Water
We often take water for granted, especially when we have had such a wet summer as this summer.  We are soon reminded, however, when we have a hose-pipe ban how precious it is.  Rather than simply letting water run off the roof and into the street, simply fitting a cistern to your drain pipes in the form of a "rainwater harvester" allows you to supply water for toilets, the washing machine and dishwasher without tapping into the piped water supply.  After all, you don't need drinking quality water for the loo.  Tommy's house has a 3,700 litre cistern buried in the garden.

Building Materials
The ground floor of the house was made from a lightweight building material called aircrete.  Among its special qualities are having excellent insulation and being very easy to use - it is possible to cut aircrete with hand-tools, yet it is strong enough to build with.

For the first floor, rather than using brick, the eco house used sustainable FSC timber.  FSC (Forest Stewardship Council) timber comes from certified forests and are managed to ensure long term timber supplies while also protecting the environment and the lives of forest-dependent peoples.  It is become easier to find this timber, even in your local DIY store, you just need to look for the FSC logo.