The International Passive House Standard is the world leader in building energy efficiency. Such buildings are known for unsurpassed thermal comfort and indoor air quality with minimal operating costs. This building standard is achievable today in North America, at an affordable price, with no ‘green premium’. The Bernhardt Passive House is a demonstration of that reality.
Plumbing, Heating and Ventilation
A critical component of a Passive House building is a highly efficient Heat Recovery Ventilation system. Modern systems are able to silently provide a constant supply of fresh air while consuming a minimal amount of energy to operate. Windows and doors provide natural ventilation whenever solar heat is plentiful (most of the year), but the HRV will operate most of the time. One HRV will service both suites and will cost $3-4/ month to operate continuously. A Zehnder ComfoAir 550 HRV will provide continuous ventilation for the residence.
For this project we selected an Eco King condensing combi boiler with an indirect hot water tank and worked with FortisBC and Bernhardt to fit all of the mechanical systems into a space the size of a closet. Electricity could have been our energy source for hot water and space heating. An electric hot water tank and heating coil costs less than gas to purchase and would not reduce thermal comfort. We chose gas because of its efficiency, lower life cycle costs and superior hot water production. A boiler and indirect hot water tank is perhaps the most expensive system to install, but it eliminates the “cold sandwich” effect of a tankless heater and ensures an adequate flow of hot water for two families.
Plumbing for a passive house is similar to any other residence, but some care is required to minimize building envelope penetrations and ensure the system design has all heat sources inside the thermal envelope.
We are proud to be part of this demonstration of affordable and sustainable construction and look forward to working with further high performance buildings.