What is Passive House?

Originally developed in Germany where it is called "Passivhaus," Passive House is a building system that is designed to create a very well-insulated, virtually air-tight building that is primarily heated by passive solar gain and by internal gains (from people, electrical equipment, etc). Energy losses are minimized, and any remaining heat demand is provided by an extremely small source. Avoidance of heat gain through shading and window orientation also helps to limit any cooling load, which is similarly minimized. An energy recovery ventilator provides a constant, balanced fresh air supply. The result is an impressive system that not only saves up to 90% of space heating costs, but also provides excellent indoor air quality.
(source: Passive House Institute US)

Is Passive House Cost Efficient?

Yes.  The extra costs associated with initially implementing a Passive House system (such as more heat insulation, special window frames and glass, and airtight implementation), are quickly offset by the lower budget HVAC system and the energy bill, which is four to ten times lower then in a conventional house.

How Does Passive House Compare with LEED?

The United States Green Building Council’s LEED certification (Leadership in Energy and Environmental Design) is the most popular sustainable building standard in the United States.  While it has opened the door for a more mainstream acceptance of green building, it also faces severe limitations.  Percentage wise, LEED buildings are found to use 25-30%  less energy than non-LEED buildings. Passive House buildings, on the other hand, can slash the heating energy consumption of buildings by up to 90% percent, and overall energy consumption by 60-70%.  Taking into account air transitions within the building, thermal heat bridging, and overall air quality, Passive House is the most rigorous energy standard in the world.  This is a strong argument that Passive House is a better standard for a carbon neutral future.  

Keep in mind, however, that a building can obtain LEED certification and also meet the Passive House standard.

Where are Buildings That Use the Passive House Standard?

There are now more than 10,000 buildings across the world certified to Passive House standard, ranging from small individual houses to office buildings, schools, and shops. A large number of these are in Germany and Austria; even the European Union has adopted Passive House standards in its policy making. only 30-40 buildings in the US have been built to this standard so far.

Where are More Passive House Resources?

The Passive House Institute, US:  http://www.phalliance.com/
Passive House feature on NPR (audio): http://hereandnow.wbur.org/2010/11/29/passive-house
Passive House in the New York Times: http://www.nytimes.com/2010/09/26/business/energy-environment/26smart.html

Building the First Passive House in Texas

Passive House on CNN

Insulating a Passive House Intro