What is a passive house?
“Maximising the use of solar energy
and minimising heat loss is our credo.”
Rolph Disch
A passive house is a building in which a comfortable interior climate can be maintained without active heating and cooling systems. The house heats and cools itself, hence “passive”.
Passive solar building design uses the structure's windows, walls, and floors to collect, store, and distribute the sun's heat in winter and reject solar heat in summer. It can also maximize the use of sunlight for interior illumination.
The technology is called passive solar design, or climatic design. Unlike active solar heating systems, it doesn't involve the use of mechanical and electrical devices — such as pumps, fans, or electrical controls — to circulate the solar heat. Buildings thus designed incorporate large south-facing windows and construction materials that absorb and slowly release the sun's heat. The longest walls run from east to west. In most climates, passive solar designs also must block intense summer solar heat. They typically incorporate natural ventilation and roof overhangs to block the sun's strongest rays during that season.
"Day lighting" takes advantage of natural sunlight, through well-placed windows and specialized floor plans, to brighten up a building's interior.
Passive solar design can be used in most parts of the world.
In the United Kingdom, an average new house built to the Passive House standard would use 77% less energy for space heating, compared to the Building Regulations.
In Ireland, it is calculated that a typical house built to the Passive House standard instead of the 2002 Building Regulations would consume 85% less energy for space heating and cut space-heating related carbon emissions by 94%.
The first Passivhaus buildings were built in Darmstadt, Germany, in 1990, and occupied the following year. In September 1996 the Passivhaus-Institut was founded in Darmstadt to promote and control the standard. More than 6,000 Passivhaus buildings have been constructed in Europe, most of them in Germany and Austria, with others in various countries worldwide. In North America the first Passivhaus was built in Urbana, Illinois in 2003, and the first to be certified was built at Waldsee, Minnesota, in 2006.
In the United States, a house built to the Passive House standard results in a building that requires between 75 and 95% less energy for space heating and cooling than current new buildings that meet today's US energy efficiency codes. The Passivhaus in the German Language Village, Waldsee, in Minnesota uses 85% less energy than a normal house of its size.