MartineHamiltonKnight.jpg "Ground floor. Copyright Martine Hamilton Knight")
Follow Zero Carbon House on Twitter!Quick notes on the ways the design avoids the use of fossil-fuel energy
Thermal insulation: the new roof and walls are 20 times better insulated than the existing ones.
Airtightness: sealed to a level 28 times better than existing, but retaining vapour permeability to stop condensation. This includes using a special membrane in the walls. Research shows that limiting warm air leakage, even through concrete walls, is an essential element of radically reducing heating needs.
Windows: triple glazing, 12 times more insulating than the current windows.
Heavy construction: stores heat and cool to keep the house warm in winter and cool in the summer.
Passive solar: glazing to provide winter solar gains. Summer shading with the existing ash tree.
Low-energy lighting and A++ fittings to minimise electricity use, including an electric cooker with induction hob.
Solar roof: photovoltaic (PV) panels convert the sun’s energy into electricity and any surplus is exported to the national grid. This offsets the electricity that is imported (for example at night).
Solar hot water: roof panels use the sun to heat hot water, stored in a large cylinder.
Ventilation system: supplies fresh air warmed by recovering 95% of the heat from extracted stale air. Another essential element in preventing heat loss.
Wood-burning stove: top-up space and water heating fuelled by wood from the garden. The heating needs are so low that prunings from the large ash tree are sufficient. The regrowth of the trees captures the carbon dioxide emitted by the stove.
Are you using the heated water directly or are you using the heat store principle?
What ventilation system are you using?
Its a heat store of 1000 litres, ie about 5x a normal domestic cylinder. Our solar panels on the roof will fill the tank with hot water. The large size of the store is so that even in winter on frosty/sunny days we hope to get a reasonable input, which will tide us over if we then get a number of cloudy days. Its been put together by GreenShop Solar http://www.greenshopsolar.co.uk/
The ventilation system is mechanical ventilation heat recovery as used in German Passivhaus design and is made by Itho http://www.itho.co.uk/Products/HRU_ECO_4/Default.aspx?id=19
System designed by The Green Building Store http://www.greenbuildingstore.co.uk/ but we have added a special heater battery so the solar store can add heat into the mvhr if required
I see on the Ecoflap site that you used their letterplate for draught exclusion, but it is not mentioned here. Did you find it useful?
Yes, it is an excellent product, see http://www.ecoflap.co.uk/
Our letterbox is triple-sealed. It consists of an outer brass flap (not airtight, but hard-wearing and matching our reclaimed brass door hanles), then the Ecoflap inside (very good airtightness). Letters go into an internal compartment with a further air-sealed internal door.