Passive houses at Portvakten Söder

The passive housing at Portvakten Söder in Växjö comprises rental flats offering innovative, modern and environmentally-friendly living.

Hyresbostäder’s distric of Portvakten are unique timber houses – eight floors buildings with passive house technique. The blocks are therefore unique in two ways thanks to their height and construction. A passive house is built without a traditional heating system and is completely sealed. The windows are super-insulated and the heat in exhaust air is recovered to reduce the amount of energy supplied. The heat produced by the residents, domestic appliances and lamps is kept inside the apartment due to the sealed and much insulated construction, which minimizes heat losses. Building with timber Timber is durable, environmental friendly, can be recycled and is one of our country’s largest natural resources. By building homes with timber, we take the environment into consideration – timber houses are environementally friendly and stable. Solid wood provides god acoustic comfort. Design of apartments In the district of Portvakten Söder there are 64 apartments as follows: 18 units: 2 rooms and kitchen, approx. 60m2 30 units: 3 rooms and kitchen, approx. 80m2 16 units: 4 rooms and kitchen, approx. 95m2 Frame The frame is of solid wood. The wall units are approx. 53cm thick including facing cement fiberboard. The beam units are 51cm thick. Approx. 30 tie-rods through each apartment block. Energy Estimated energy consumption is 50kWh/m2 of which heating is 15, hot water 25 and property electricity is 10. This excludes household electricity that normally amounts to approx.. 40 kWh/year. The outgoing drainage water pre-heats the incoming cold water, that later will be hot water, in a special drainage heat exchanger. Transmission losses Maximal permissible level of heat losses through the climate shell is 10W/m2. Ventilation 85% heat recovery. Double plate heat exchangers. Additional peak heat from heat batteries connected to the district heating in each apartment. Individual metering Individual metering of cold water, hot water, household electricity to each apartment. The consumption can be followed on a display in each apartment. Windows Triple glazing with argon gas filling and solar protection glass.