For a building to be considered a Passive House, it must meet the following criteria:
1. The Space Heating Energy Demand is not to exceed 15 kWh per square meter of net living space (treated floor area) per year or 10 W per square meter peak demand.
2. The Primary Energy Demand, the total energy to be used for all domestic applications (heating, hot water and domestic electricity) must not exceed 120 kWh per square meter of treated floor area per year.
3. In terms of Airtightness, a maximum of 0.6 air changes per hour at 50 Pascals pressure (ACH50), as verified with an onsite pressure test (in both pressurized and depressurized states).
4. Thermal comfort must be met for all living areas during winter as well as in summer, with not more than 10 % of the hours in a given year over 25 °C.
How did PassiveHaus start?
A German physicist was looking to build his own house. After looking at the way we build houses, he set about understanding the science of what makes an energy effect building. And created the Passive Haus standard. Which is an independent, non-for profit and open sourced institute.
The first houses built to Passivhaus standard were completed in 1991, and since then over 10,000 houses, schools, offices etc have been constructed to the standard in Europe, USA and many other parts of the world. There has been extensive monitoring of Passivhaus buildings which has demonstrated conclusively that they deliver what they promise. The design specifies that heating load should be no more than 15 kWh/m2/year, and the data confirms this. Of course there is a range, depending on lifestyle, but studies have repeatedly shown that the median value is always at the design figure. (the green building store)
“It saves up to 90 percent of the building’s overall energy consumption when compared to a standard house constructed to current building regulations”. (Federation of Master Builder)
THE PASSIVE HOUSE INSTITUTE
The tried and tested Passive House approach is widespread in Germany and Austria. The first Passive House project was built in Germany in 1990 and there are now an estimated 30,000 Passive Houses across Europe.
The Passive House Institute (PHI) was founded in 1996 by the concepts cocreator, Professor Wolfgang Feist. Based in Darmstadt, Germany the Institute has developed the Passive House Standard through extensive research and monitoring of thousands of Passive House projects