What is a passive house?
A passive house is a energy performance standard which seeks to maximise the energy efficiency of buildings, the definition states that a passive house energy demand must not exceed 10W/m² for heating net living space in heating or cooling. This means that in mild climates like Ireland the house does not have to be heated for the vast majority of the year.
The passive standard is purely an energy performance rating like the fuel consumption of a car. It does not take into account the energy required to build the house or how natural/sustainable its materials are. We think it is important to not surround ourselves with plastics and glues but have an internal environment with natural materials such as wood and stone wool insulation.
The criteria for a Passive House per m² living area:
- Max. 10 W/m² constant heating-load or
- Max. 15 kWh/(m²a) annual space-heat requirement
- Max. 42 kWh/(m2a) annual total amount of active energy input
- Max. 120 kWh/(m2a) total energy requirement for space-heating, domestic hot water and household appliances
How to build a passive house
Never having to spend money on heating the house is a very attractive concept. To reach this very high level of performance one could expect that the building costs would increase sharply. This does not have to be the case. The costs are not excessive as long as the design and orientation of the house are carefully considered. Some general points about design:
- Consider a bulky shape with minimal surface area.
- Large windows to south – none to north.
- As few external doors as possible.
- One roof-half in direction true south for solar collectors.
- Consider building a single-storey house.
- Consider building a duplex with two or more apartments in one body.
The building procedure would be much the same as for any Scandinavian Homes house. The foundation with all insulation is done by us. The shell with triple glazing and felted roof is made by us. The only difference is that the added 70mm of studs (for passive) or 120mm insulation plus 70mm studs (for super passive) and insulation in the external walls would have to be done by your local finishing carpenter and the cellulose fiber insulation contractor.
Please contact us to develop your ideas. Generally, any single storey Baltica, Nordica or Hibernia house would be suitable. The compact shape of a true two-storey house provides a good bulky shape with minimal surface area. All the two storey types in the Utklippan, Kattegatt, Skagerack and Draget Series are suitable. When two-storey designs are built to passive standard the challenge is to make it airtight. It is much more demanding for the finishing team compared to build a single storey version.