What is a passive house or Energy Zero House?
This is a structure that has a heat load (energy requirement of a maximum of 15kw hr/sm/yr). In other words it is so well insulated and the energy within the house is stored so well that it requires only the minimum extra energy to heat water etc. The space heating is looked after by, solar gain through windows etc., the human activity within the building (each person gives off nearly 1/3 kw.), cooking, showers etc all give off heat to the house. Only the very smallest amount of energy will be required for the Irish weather to maintain the necessary heat levels in the house. It is then recycled time and time again using the heat recovery system. Water heating is achieved with solar panels, small boiler and with a heat pump linked to the ventilation system. It is very difficult to construct an Energy Zero house free building on site. We have seen how the problems of on site construction can seriously prejudice achieving theoretical u-values. While this is a disadvantage for a Low energy
