Building Capability for Building Passive Houses

A while back I wrote about the Passive House concept – housing design so efficient that a conventional furnace is not required. “It incorporates efficient building shape, solar exposure, super- insulation, advanced windows, leading-edge ventilation, and other technical features to create structures that use 80 to 90 per cent less energy than conventional new homes.” The idea continues to attract more attention among builders.

An article published in March, 2011 reported on a home in Ottawa that has been certified as the first Passive House in Canada. “Chris Stratka of Vert Design was intent on building a super-insulated home when he bought the property in the New Edinburgh neighbourhood of Ottawa… when he took the design to a Passive House consultant he was told it probably wouldn’t qualify because the building materials and systems available in Canada that he had specified were seen by the consultant as inferior to those available in Europe.”  (There are 25,000 Passive Houses in Europe.)

He decided to do the best he could. His strategy was to work with a modular home builder who would construct components using his insulation specifications. The basic structure was assembled on-site in three weeks with minimal disruption to the neighbourhood.

A green building specialist provided third-party inspection, testing and verification services. During construction, the house was tested for leaks several times to identify any leakages. The results suggested that the Ottawa home just might qualify for Passive House certification after all. All passive house components were intentionally sourced within North America to prove that the capability exists here. (click to view specifications in PDF)

Back in Toronto, an article in the Toronto Star reported on the difficulties being encountered by a builder there who wanted to be the first in the city to create a Passive House. “There are so many innovative features involved in a Passive House that it makes the approval process slow and frustrating… the original plan was to retain the existing basement and subfloor, then build all-new exterior walls using a system of foam-insulated frames that deliver a whopping R-50 of insulation. Trouble is, this one feature alone requires individual approval for use in North York involving a process that could take weeks or months.”  The other stumbling block in Toronto involved a Heat Recovery Ventilator (HRV). While the Ottawa house sourced this component from London, ON, the Toronto project opted for a German-made model on the advice that Canadian versions weren’t efficient enough. The trouble is, considerable time and cost is involved to have the imported model certified for use in Canada.

The article concluded that “the ability to efficiently assess and approve homebuilding innovations needs to become one of our most important skills as a society.

The experiences in Ottawa and Toronto suggest that:

  • domestic capabilities are being under-estimated in favour of the market leaders in Europe
  • off-site construction of modular framing components may be the way to go
  • repeated air leak testing during the construction process is a vital step in achieving quality results
  • current municipal approval processes are way behind technology innovations
  • adding more, and better, insulation is probably the best initial home improvement for existing homeowners

In January, 2012, a new National Building Code comes into effect that will raise the minimum building standard to the EnerGuide level of 80% efficiency. The industry innovators are demonstrating that it’s already possible to substantially exceed that goal. “A new factory-built bungalow in Dartmouth has been deemed the most energy-efficient home in Nova Scotia, and it could cost a homeowner virtually nothing to run… It has an EnerGuide efficiency rating of 94 per cent — the highest in the province. … The bungalow is about $50,000 more than a regular pre-built home.”

The challenge now is to make these innovations economically affordable to a larger segment of homebuyers. Since Innisfil will be creating a commercial centre as well as growing by about 40,000 new residents over the next few decades, we may have an opportunity to help lead the way to sustainable, energy efficient building techniques. The benefits of combining new standards, new skills, and new materials would impact the whole community.

References:

A Tour of the First “Passive House Certified” Residence in Canada, March 8, 2011

Bureaucracy a roadblock to green innovations, Steve Maxwell, July 15, 2011

Dartmouth home boasts highest EnerGuide rating, August 19, 2011

Staying Warm Without Using Fossil Fuels, Our Innisfil, January 2011

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