This term was created by Professors Bo Adamson, a sweden enginneer, and Wolfgang Feist, a german engineer, and the first passivhaus was built in Darmstadt, Germany, in 1990. Dr Feist founded the Passivhaus Institute a few years later, in 1996.
What makes a passivhaus so different than an ordinary house?
The thermal comfort of the passivhaus is guaranteed solely by re-heating (or re-cooling) the fresh air that is required for satisfactory air quality. This means that there is no heating system, except for heat recovery through the ventilation unit.
Houses are built accordingly to five key principles:
1. Wall insulation - thick layers of insulation (around 40 centimeters expanded plastic) to prevent heat losses.
2. Windows - small percentage of the surface area occupied by glass windows. Large windows should be to the south to maximise incoming light and heat from the sun in Winter. 40 per cent of the total winter heating should come from the sun.
3. Bridges that conduct cold into the houses are avoided by using special prefabricated materials.
4. Airtightness - refers to the loss of air through cracks, airbricks, poor door seals, windows. Passivhaus must loose less than 60 % of the volume of air in the house per hour. This can be achieved in pre-fabricated houses with factory made components that fit together very tightly.
5. Ventilation system - mandatory for air renovation. In the winter, cold air that enters passes over ducts containing warm and humid air leaving the building.
Passivhaus diagram
Energy requirements comparisonThe diagram was downloaded from 100k House
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