“Sjunde huset” (The Seventh House) in Tuolluvaara, just outside Kiruna, is Sweden’s northernmost passive house.
"Sjunde huset" was a collaborative project between NCC, Kiruna municipality and Luleå University of Technology. The semi-detached house is based on NCC’s concept of energy-efficient and environmentally-friendly houses. The building has a wooden framework and contains two 140 m2 apartments. Each apartment is equipped with solar panels of approx. 15 m2, which are placed on the building’s façade for optimum effect as, during the winter, the reflection of light from the snow on the ground increases the production of electricity.
The building has been erected in Tuolluvaara, which will become part of the new Kiruna. The climate here is classified as Arctic/subarctic.
The buildings are heated using airborne heat, with an efficiency of above 80 %. District heating supplies the ventilation unit’s thermal battery, washing machines, tumble dryers and dishwashers. The district heating network is laid together with the water and sewage pipes. Each apartment has two energy-smart showers, which provide an approximate saving of 1,750 kWh/year. The water from the showers is purified in a filtering system and recirculated. The specific energy usage has been estimated at approximately 50 kWh/m2/year. Energy usage excluding household electricity is estimated at 7,000 kWh/year.