It increasingly seems that Canada is falling behind advances in the design and construction of sustainable buildings when compared to the achievements made in other countries. This is no more evident than in the case of passive houses.
A passive house is defined as 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” (Defn. Passiv Hause Institut). It is also a voluntary, standard for energy efficiency developed in Germany (Passivhaus) that is derived from an integrated design process. (Defn. The Energy Challenge: Directory Passive Houses ). It is a house that requires no furnace and no air conditioning system.
The first Passive House was built in 1991 in Darmstadt Kranichstein, Germany by Dr. Wolfgang Feist founder of the Passive House Institute. With Dr. Feist as the initial driving force, the Institute and the European community have established a Passive House standard that has been extensively researched and widely accepted in Europe. There are now considered to be more than 20,000 passive houses around the World, about 12,000 in Germany, Austria and Scandanavia.
The European Parliament has adopted a requirement that all new buildings that need to be heated and/or cooled be constructed to the passive house standard beginning in 2008, and non-residential buildings from 2011.
While Europe and Scandanavia have charged ahead with Passive House development, the first house designed and constructed to the Passive House specification in Canada was in 2006. It was built in Gatineau, Quebec by Malcolm Isaacs a civil engineer who is now a consultant, advocate and trainer in Passive House construction techniques, thermal analysis and energy modeling. Photos’s of Isaacs house construction can be found a Flickr.com.
Isaac explained at a recent Passive House presentation organized by the Ottawa Green Building Council that passive house design focuses on creating an extraordinarily well sealed building envelop by using a combination of insulation, high-tech window and door design and airtight construction. Thermal bridging from any source is eliminated with construction of a sandwich like exterior wall (details to follow in a future article).
Unlike typical energy efficient house design in North America that recirculate air which leads to stale air, mould and other problems, passive houses have a constant supply of fresh air, as well as windows that open (on the north side as well) and self-regulating airflow.
Passive houses also are sited to take advantage of passive solar gains and minimize cold northern exposure.
Passive houses are usually smaller than conventional houses in order to achieve the energy efficiency criteria of the standard. Passive house size would likely encounter consumer resistance in Canada and the U.S.
The Passivhaus standard for central Europe requires that the building fulfill the following requirements. Passive houses built in Scandanavian countries are constructed to a higher standard.
- The building must not use more than 15 kWh/m² per year in heating and cooling energy.
- Total energy consumption must not be more than 42 kWh/m² per year
- Total primary energy consumption must not be more than 120 kWh/m² per year
The following list of links is to further emphasis the scope of the interest in passive houses:
The Passive-On Project – Passive-On is a completed research and dissemination project which was funded within the Intelligent Energy for Europe SAVE programme. The project worked to promote Passive Houses and the Passivhaus Standard in warm climates.
New York Times article, No Furnaces but Heat Aplenty in ‘Passive Houses’, December 27, 2008
In Canada there is the Net-Zero Energy Home Coallition and CMHC ‘s demonstration Equilibrium Housing program. Both organizations offer innovative and promising approachs to sustainable housing but still seem a long way from reaching the housing market or achieving the Passive House standard. The Canada Green Building Council is also working on a LEED rating system for homes that is yet to be launched.
There is The Passive House Institute in the US and the third annual North America passive house conference was held in December 2008.
It is evident that the passive home standard and methodology is proven, becoming established in other jurisdictions, and seemingly years ahead of Canadian house building technique. This may be a bandwagon where Canada should consider jumping aboard.
An immediate and timely source of more information about Passive Houses is the 13th International Conference on Passive Houses to take place on 17th and 18th April 2009 in Frankfurt in Germany. People who don’t speak German will be provided with headsets, simultaneous translation and an English version of the presentations.
According to Malcolm Isaacs when he last attended this event he was one of the few, if not the only Canadian present. It is time Canadian attendance at this conference and attention to passive houses reflected the interest it deserves from our design and construction industry.