Evelyne Bouchard of Hemmingford says that when she tells people she specializes in passive house design, they often think she is “doing 1970s-style eco-houses.” However, the current Passive House Standard actually refers to an international energy efficiency standard. Established in 1991, that standard (also known as Passivhaus) can be applied to all types of buildings, from houses to commercial and institutional buildings, and remains the most energy-efficient model in the world.
The basis of passive house design involves the maximization of efficiency by means of minimizing heat loss, Bouchard says, making “the shell of the building like a thermos.” This is achieved through continuous insulation, improved airtightness, triple-glazed windows, and a ventilation system with heat recovery. All these can reduce energy consumption related to heating and cooling by 75 to 90 per cent. Not only does this efficiency preserve resources, but it also creates a living space that is “really comfortable,” she explains.
Bouchard and her family moved into their own passive home at the beginning of last winter – designed and coordinated by Bouchard herself, of course. She describes a cozy January spent in shirtsleeves and their trio of cats basking in sunbeams, without the house’s heating system even engaging despite the frigid temperatures outside.
Passive house principles can also be applied to the renovation of existing buildings. Bouchard explains that following a “logical sequence” is particularly important if one plans on spreading out the renovations over a longer span of time. For example, the first step might be installing a ventilation system with heat recovery (if the building does not already have one), then making the building shell more airtight, then adding insulation. Doing the work in this sequence ensures good indoor air quality and reduces the risk of mold and condensation forming in the walls and attic. Replacing windows can also significantly improve energy efficiency and comfort: “The windows are the weakest link,” Bouchard says.
Whether a homeowner’s approach is all-at-once or gradual, the benefits remain the same. Passive house design “ties into climate action in two ways,” Bouchard says. The first is by mitigation, or reducing the environmental impact of the building by drastically reducing the energy used for heating and cooling. The second is adaptation, since a house that requires less input/resources is more resilient. “It’s reassuring to think that you can get through something like the [1998] ice storm” with far less difficulty, she says, having endured that event while she was in high school.
Empowering studies
After attending Chateauguay Valley Regional High School (CVR) and Dawson College, Bouchard obtained a master’s degree in architecture from McGill University, and then moved to British Columbia with her then-partner-and-later-husband Jeff Turner. While she was working for an architecture firm in Vancouver, where she says she did “run-of-the-mill stuff,” she signed up for a night course on passive house design and construction at the University of British Columbia, where she says she “really lucked out.” She says those studies with Dr. Guido Wimmers, who is an international authority on passive house design and worked on the Austrian pavilion for the 2010 Olympics (the first Passivhaus-certified building in Canada), “filled in a lot of things [she] hadn’t learned at university.” Turning her focus to this approach to architecture was “empowering, in a way,” she says, explaining that she felt she was “going back to the core principles.” She adds that she feels fortunate that she “happened to find it at the right moment.”
After returning to the Valley in 2017 with a newborn in tow, Bouchard launched her own architectural practice, called Tandem Architecture Écologique. In addition to her practice’s projects, she is the vice-chair of the board of directors of Passive House Canada, and is a course lecturer at the Peter Guo-hua Fu School of Architecture at McGill University. She is also a course instructor for Passive House Canada.
Doable projects
Working in this field in Quebec is not without its challenges. The low price of electricity means that owners may not feel a great urgency to update their buildings or systems, and the passive house design is relatively new here. The lack of public knowledge about it means some people dismiss it out of hand as being unsuitable. “I’d love to demystify it [for people],” Bouchard says, “It’s not as esoteric as people think.”
Building her own home was heartening in terms of confirming how doable passive house projects are right here in the Valley “if you find a [construction crew] with the right mindset.” She says that the great work done by Hemmingford-based companies Myden Construction and JCD Construction, and cellulose insulation installed by Howick-based Isolation TK, was a “good example of local people who rose to the challenge of something unusual.”
As knowledge of passive house design grows, it is likely that its “efficiency-first” principles will become far less unusual across the Valley and beyond. Those wishing to learn more about the approach can visit www.passivehousecanada.com or https://en.tandemarch.ca.