Sunday, 9 August 2009

Design Aspects of the Riseley Eco House


The Riseley Eco House would use insulation at a thickness of 300mm.

Airtight construction

The Riseley Eco House would be built to an air tightness of 3 air changes per hour at 50 pascals test pressure. Using a high performance vapour permeable breather membrane the timber frame is encapsulated to quickly achieve an airtight and water tight envelope on the building.

Thermal mass

In winter any warmth generated within the house from cooking, people or passive solar gain can be used to warm the floors and walls creating a heat store ensuring a naturally comfortable internal environment. In summer night time cooling of the storage capacity of the thermal mass can be used to keep the building comfortably cool. As climate changes deliver warmer summers, this becomes an increasingly important consideration. The residual heat load is so small that a small amount of renewable wood burnt in a wood burning stove should be all that is needed to provide domestic hot water in winter.

Low water usage fittings

A significant saving in water would be made by fitting water saving taps and shower fittings. High quality fittings save water by aerating the water flow. This makes it appear that there is a large volume of water coming out of the tap as well as making the water feel 'soft', but in actual fact the volume of water is very low. High quality low water shower heads work on a similar principle.

Green roof

The Riseley Eco House would have a north facing green roof, sloping up from the High Street. The growing surfaces on the roof provide habitat for insects, in turn benefiting the local ecosystem and offsetting the habitat loss of the building’s foot print and helping it “disappear”. The green roof also helps reduce surface water runoff.


The Riseley Eco House would be orientated North-South. South facing homes have lower winter fuel consumption than ones facing East West. High performance full height windows South facing would ensure that large areas of glazing could be used to give excellent daylight and good solar gain (with roof overhang shading to prevent summer overheating). With the southerly aspect incorporating a “sunspace” the glazing could achieve a net gain in energy over the year, whereas North facing glazing a net loss. Over heating would be overcome by the roof overhang solar shading in conjunction with ventilation

Photovoltaic panels

Photovoltaic panels convert the sun's energy into electricity and any surplus can be sold to the national grid. With 21 Photovoltaic PV panels the Riseley Eco House would meet its consumer energy load, generating enough electricity for all lighting and appliance use within the house. This is the mandatory energy use requirements for meeting CFSH level 6. The PV panels would be on the lower south facing roof and would not be visible from the High Street.

Low energy lighting

A mixture of compact fluorescent and LED light fittings would be specified in the Riseley Eco House.

Rainwater harvesting

A rain water harvesting tank would be sunk under the garden. The tank stores rain water fed directly from the roof to be used in non potable applications such as toilet flushing and garden irrigation.

Solar hot water

Solar thermal panels on the south facing lower roof (not visible from the High Street) would use the sun's energy to heat water. In mid winter top up hot water could be supplied from the wood burner. A 700 litre dual coil hot water tank could store enough hot water for the whole family all day and make the most of the solar thermal panels.

1 comment:

  1. A lot of energy is wasted in a house if it's not properly heated and insulated.