With an impressive 0.03 ACH @50 Pa airtightness result, Kilkenny is the first Passive House to apply for certification in the Southeastern Ontario region
The Kilkenny Passive House was built with one purpose in mind: to achieve Passive House Institute certification. Passive House-Certified Designer and PHC member Brock Wilson discusses the project and what it means to the Southeastern Ontario area.
After a series of jumps, in 2021 Brock Wilson started Wilson Architectural Design, the same year he received his Passive House designer/consultant certification.
Can you describe the Kilkenny PH?
Kilkenny is a semi-detached, roughly 1,200 square foot (per unit) two-storey building. Each unit is two bedrooms. The client, Alex Liolios of Zero Energy Homes (also the contractor), really had a vision, and that’s how we’ve approached this project from the beginning. Alex is one of the only [Passive House] certified tradespersons in the area. This was one of his first ever [PH] builds, and his vision from day one was certification.
The site was quite small, so we really utilized as much buildable area as we could. From a design aspect, it’s very simple and linear. It’s just a box area with two bedrooms upstairs and a large, open kitchen and living area on the ground floor.
I like to joke that it’s almost like a Yeti cooler because essentially, we’ve just wrapped the entire thing. We tried to modularize the design so that it cut costs and the construction was simpler, with less waste, For instance, we modularized the floor plan so that the interior dimension was about 16 feet, so it was really simple to put in some floor joists for the second floor.
We used a Legalett slab which transitions to the Nudura ICF continuous insulation, which then transitions to a fully insulated roof system. The floor system is actually hung with specialized brackets that maintain the interior continuous insulation layer and tie back into the concrete structural core of the ICF block. I would say the airtightness came down more to the execution of the installation of the windows and the air tightness layer. We also used Enersign windows and doors. All in all, it’s pretty significant in terms of the envelope’s energy efficiency.
For our first blow door test we got a result of 0.01 air changes per hour at 50 pascals, so at first, we didn’t believe it.
What we really pride ourselves on is the air tightness ratio. Our results came in extremely low. For our first blow door test we got a result of 0.01 air changes per hour at 50 pascals, so at first, we didn’t believe it. There was some piping that was essentially taped – for the reason that it was going to be sealed at the final stages. So, that was removed just as a test measure to compare if the readings were accurate. They ended up being accurate, based on the square footage of the whole.
We were then referred to Homesol Building Solutions, an energy consultant out of Ottawa. They came in and did a blow door test again, which then scored 0.03 ach. They actually had two blow doors going at once, one on each side of the semi. Again, we were very surprised and excited about the results.
I believe they’ve sent the results off to the Energy Conservatory in the United States to confirm. Of course, obviously, we want to make sure that it’s legitimate, right? We’ve been waiting on a letter from the Energy Conservatory, but meanwhile, Homesol has confirmed that they’ve received positive confirmation on these results.
What makes this Passive House so significant in terms of the area?
We’re excited to potentially be the first on the map in this area in terms of Passive House certification. From east of Ottawa to here, there’s not much in terms of Passive House. In fact, as far as I know, there’s no certified projects in the area at this time. We are currently working on a small residential building in Maxville that’s hopefully going to receive low energy certification, and we’re working on a 10-unit apartment building in Cornwall, ON that’s also going for low energy certification.
We will just continue to promote Passive House in Ontario. That was one of our main goals, to just try to continue this movement towards building Passive in our area and building better, which is, I think, starting to create some traction. We’ve recently won the environmental Impact Award from the Cornwall and Area Chamber of Commerce.
We’ve recently won the environmental Impact Award from the Cornwall and Area Chamber of Commerce
How do you convince more people to build to Passive House standard?
I think education and awareness is key. Typically, everybody is set on traditional construction. Some of the contractors around this area — not to say that they’re not great contractors — tend to convince clients to construct to minimum building code with significantly less insulation. They tell clients that Passive House or low energy is not necessary. Ironically, in a couple years from now, [buildings built to] the minimum building code [of today] will not be compliant. And then, of course, a lot of individuals have this sense of cost. Again, it comes down to needing a lot of these projects and case studies to really show clients that, you know, this isn’t any more costly than building standard.
On the other hand, we’re seeing a lot of people that are stipulating, “This is our forever home.” They use that term, and they are not looking to move. That shouldn’t be the reason why people choose Passive House or low energy, but that is one reason that we’ve been seeing.