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Analysis of the recently-released design details contained in CMHC’s can be considered from two distinct perspectives; building process and operational energy efficiency.

It was clear from the outset the catalogue’s basic intent was never to be all things to all people or all types of home development. Instead, its intent was to encourage more streamlined approval and construction of urban infill and accessory housing. In this respect, there is a fairly broad consensus of acceptance by both the building industry and energy efficiency experts.

To begin, the building specifications for each design do not suggest a particularly high level of sophistication. That’s understandable, Daniel Winer of told the Daily Commercial News.

“These designs support a wider range of builders, meaning we can diversify the economic opportunity that can come with this type of housing.”

Winer explained in his home province of British Columbia, the average builder completes less than six homes per year.

“Pressure to build more houses means they are being asked to double or even triple their productivity. The catalogue is meant to make the design and approval process smoother and make that jump in production more likely.”

The catalogue’s focus on traditional onsite, stick-built construction rather than more sophisticated methodologies is also understandable, Winer continued.

“I imagine a push for a particular construction form would have also been viewed as government overreach.”

He believes it is appropriate at this opening point to focus on implementation of the infill building initiative rather than on construction methods.

“If we can get implementation processes right, then further designs could be created to support alternative building methods.”

At the same, Winer notes municipalities must weigh in with improved consistency in zoning bylaws and lot sizes, without which it will be difficult for any small builder to know which type of units can be built on a given lot. That would limit fast track approval uptake.

Infill housing can be a challenge even when projects fit within existing municipal guidelines. A case in point is the in Kitchener, Ont., over an approved backyard housing project that has run into strong NIMBY opposition.

Betsy Agar, director of buildings policy at , agrees with Winer the relatively low bar set for construction processes appears to, “enable less sophisticated builders to deliver on the packages.” Nevertheless, she told the Daily Commercial News the documents have, “an educational strength in terms of how they lay out operation and embodied carbon prediction modelling.”

Agar said that suggesting designs tailored to local conditions and codes make them “regionally relevant”. She also notes that by adopting Tier 3 of the , “CMHC has struck a balance between standardisation and ambition, both helping to raise industry capacity.”

For example, she says Saskatchewan recently reverted back to Tier 1 while British Columbia will adopt Tier 4 in 2027.

“The more these designs look like the codes and specifications the sector is familiar with, the more they will be implemented, and correctly.”

CEO Michael Quast told the Daily Commercial News the catalogue, “could have gone further by setting clear, measurable performance targets for energy efficiency.”

Yet he recognizes the meaningful ambitions behind the catalogue initiative.

“Rather than viewing this catalogue as an endpoint, we see it as a foundation, an opportunity to demonstrate that building better does not need to mean building slower or more expensively.”

The catalogue designs set a target of 2.6 Air Changes per Hour (ACH). While PassivHaus designs achieve 0.6 ACH, Quast is encouraged by B.C.’s Tier 4 designs which perform at 1.5 ACH or better. At the same time, component insulation values are quite high. For example, exterior walls in the catalogue’s Stacked Townhouse design for Ontario specifies exterior wall insulation of R12 foam plus R24 infill insulation. The double-glazed windows are to have a minimum U-value of 0.21.

Looking towards future iterations of the catalogue, Quast sees an opportunity to introduce improvements in building techniques aimed at energy efficiency, such as explicit air-sealing details, quality membranes and tapes and guidance for maintaining a continuous air barrier.

“With slightly higher performance benchmarks, it could also help normalize low-carbon, high-efficiency construction across the country.”

At the same time, “progress deserves recognition,” Quast said. “The catalogue moves us forward in a complex space with many stakeholders and competing priorities. The next step is to build confidence that better performance and faster, more affordable construction are not opposing goals; they’re complementary ones.

Winer agrees, saying, “The CMHC standardized design package is a great first step and presents a vision of what is possible.”

Proof of success for the catalogue will be measured by results.

As Agar put it, “I would hope that they survey the sector in six to 12 months to see how the costing they have estimated measures up to reality.”

John Bleasby is a freelance writer. Send comments and Climate and Construction column ideas to editor@dailycommercialnews.com.