Passive House is a performance standard that certifies buildings with dramatically reduced energy consumption compared to typical construction standards - the idea and the first Passive House in the world having been built in Saskatchewan Canada. The actual Passive House rating system was developed in Germany (Passivhaus) and has since made its way around the globe as a recognizable label that indicates an extremely energy efficient building.
A certified Passive House building is characterized by significant amounts of insulation and an extremely airtight building envelope. There are two separate organizations that certify homes under the ‘Passive House’ umbrella, the Passive House Institute (PHI) and Passive House Institute US (PHIUS). Read "Everything you need to know about Passive House (or Passivehaus)" here to understand the differences between the two organizations and how to select the best fit for you.
Alternatively, see everything about Passive House on EcoHome here. If you want to enjoy all the benefits of a Passive House on a budget, without the cost of the full certification process, read about the EcoHome Passive Solar Index design service here - and if you're also concerned about toxins in homes adversely affecting indoor air quality, consider aiming for LEED Platinum V4 certification instead, like the Edelweiss here.
Or you can also find more information on Architect designed prefabricated Passive House & LEED ready Kit Homes available in Quebec, Ontario, New York, Vermont, Maine or New Hampshire here.