We’ve all heard the saying “what goes around, comes around” but it doesn’t usually refer to something like a house. In this case, what comes around isn’t just your average house – it’s an extremely energy efficient, advanced home called Passive House.
Let’s go back to 1977 when a few clever folks created a super insulated, air tight home on Regina’s Rink Avenue, called the Saskatchewan Conservation House. Energy conservation was the overriding principle driving the project’s concept and execution. In this project, conservation meant using passive design approaches to minimize energy consumption at the source instead of using more energy than you need and then figuring out a way to supply that energy more efficiently. The Saskatchewan Conservation House was a pioneer in this respect and its legacy has carried forward to today, inspiring high performance building design approaches in Canada and around the world.
In 1988, two German researchers – Wolfgang Feist and Bo Adamson – researched early examples of passive design, including the Saskatchewan Conservation House, to better understand what they could do to minimize home energy consumption. The result was a comprehensive and rigorous approach to build or renovate homes and commercial buildings utilizing the current state of the art in passive design strategies. It was named Passive Haus in German and Passive House in English. Their first-ever project was completed in 1991 in Darmstadt, Germany. Since then, 3,492 Passive House projects have been completed worldwide.
In 2016, Passive House came back home to Saskatchewan with the completion of the province’s first-ever Passive House project in Saskatoon. The Temperance Street Passive House is a duplex home that is certified to meet the Passive House standard. Now, it’s Regina’s turn to embrace the Passive House design that got its start in the city nearly 40 years ago.
Layne Arthur, a Regina-based architect and an enthusiastic advocate of Passive House, is on a mission to grow the market base of these efficient new homes. “Passive House makes sense for Western Canadian homes that are concerned about energy costs and related impact on the environment,” says Layne. “It’s a comprehensive building approach that brings together all facets of design and construction to conserve energy. The end result is a well-built, high quality, comfortable home.”
What is a Passive House? It encompasses all of the potential energy usage of the home, including the building envelope, appliances, heat sources, lighting and plug loads, with the goal of minimizing energy use at its source. A Passive House is a certified home designed, built and tested to deliver an annual total energy consumption of less than 120 kwh/square meter of floor space.
Energy savings are an important consideration when considering building a Passive House certified home and these homes certainly deliver. According to Layne, expected overall energy savings would approximately 80 to 90% as compared to a typical home built to minimum building code standards.
Layne also points out that when folks are considering the benefits of a low energy home, there is one significant benefit that is often misunderstood and/or ignored – comfort. A Passive House will deliver the ultimate blend of home comfort throughout the home: no cold air drafts, no chilly feeling when you sit beside an outside wall or even a window on cold days and having the right amount of filtered, fresh air continuously circulated through every room. Passive Houses, due to their thick insulation, efficient glazing and low air leakage, minimize sound transfer from the outdoors – a big plus in noisy urban settings.
As you may expect, a Passive House will cost more to build than a standard home. However, it’s not as much as you may think, especially if a conventional heating system can be eliminated. In the end, the budget impact will depend greatly on the unique set of choices you make in planning your home. Layne’s view is that with innovative design approaches and careful component selection, he may be able to build a Passive House with a modest premium of 5-8%. “Your energy savings over time should more than offset the extra up-front cost,” says Layne.
Of course, there are potential challenges with any construction project, including Passive House. Layne suggests there are a few things to consider at the start. Site analysis is one of these, including the site’s sunlight exposure and any site layout issues. These can have a significant impact on the project’s energy requirements. Also, the Passive House protocol must be followed in each phase of the project. For example, during the construction phase rigorous attention must be paid to air tightness to ensure the home will meet Passive House performance criteria. Layne suggests that blower door tests are employed prior to the installation of final wall finishes ensuring that any air leaks can be corrected beforehand. Quality control and buy-in from the entire project team are critical to a successful Passive House project.
Whether you are looking at a major renovation or a building a new home and want to minimize your energy footprint, Passive House is a viable option. To learn more, your next step could be a chat with a certified Passive House designer. These folks, such as Layne Arthur, have the knowledge and skills to be able to answer your questions. Layne’s current project is his own Passive House with construction starting this spring. Once completed, he will offer tours of his new home and will publish its ongoing operating performance. Further down the road, his sights are set on also promoting the benefits of Passive House certification for commercial or institutional buildings. Passive House may have been nurtured in Germany, but it has its roots firmly planted in Saskatchewan.
How does a Passive Home differ from today’s standard building practice? Here are a few differences:
Extremely low air leakage, below 0.6 air changes per hour (ACH) at 50 Pa as measured by a standard blower door test. For comparison, a top quality custom home, if built with special attention to minimizing air leakage, would likely deliver between 2 to 3 ACH at 50 Pa. The less air that leaks into your home, the less energy you need to heat it.
Continuous insulation, and lots of it. Expect an uninterrupted insulation barrier enveloping the entire home, including concrete floor slabs, foundation and footings. Elimination of thermally conductive pathways such as bare concrete foundation walls or even wood wall studs that draw heat from the inside drywall through to the outdoor sheathing.
Special triple pane windows with well-insulated frames.
A heat recovery ventilator to carefully deliver fresh air to each room and recover waste heat before the exhaust air is vented outside1.
Building design strategies to maximize energy conservation suited to local and site conditions.
