For most of the past five years, St. Hilda’s Towers has been the subject of a so-called 'deep retrofit' meant to make the 350-apartment complex much more energy efficient, comfortable and safe, especially from the kind of high-rise fire that ravaged a low-income London high-rise known as Grenfell Tower in 2017.Riley Snelling/Riley Snelling Photography
For about 50 years, the three brick towers have loomed large over the intersection of Dufferin Avenue and Eglinton Avenue West in Toronto, a monument to a previous generation’s ambition to provide affordable housing for low-income seniors.
But for most of the past five years, St. Hilda’s Towers has been the subject of a very different type of ambition – a so-called “deep retrofit” meant to make the 350-apartment complex much more energy efficient, comfortable and safe, especially from the kind of high-rise fire that ravaged a low-income London high-rise known as Grenfell Tower in 2017.
Financed by the City, the Ontario government and Canada Mortgage and Housing on behalf of non-profit operator WoodGreen, the St. Hilda’s project is nearing completion: the first phase was finished last year and tenants whose apartments are in the second phase will be moving back later this fall, according to the project design leads, Graeme Stewart and Ya’el Santopinto, both principals with ERA Architects.
Among many other improvements, the retrofit included building-wide sprinkler systems, including in common areas, and new interior insulation panels that rely on a specialized noncombustible product made with Rockwool, a stone wool batt produced by a Danish firm.
“It’s a significant amount of work,” says Mr. Stewart. Adds Ms Santopinto: “I think that really points to a critical weakness in our system currently, which is that we have funds for accessibility and decarbonization. [But] when owners need to make those kinds of safety improvements it’s typically going to be out of their pockets.”
St. Hildas's Towers transformation. For most of the past five years, St. Hilda’s Towers has been the subject of a so-called “deep retrofit” meant to make the 350-apartment complex much more energy efficient, comfortable and safe, especially from the kind of high rise fire that ravaged a low-income London high-rise known as Grenfell Tower in 2017.Riley Snelling/Riley Snelling Photography
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This is the second such affordable housing deep retrofit for Mr. Stewart and Ms. Santopinto, whose practice focuses on renewing aging apartment complexes; their first was the Ken Soble Tower in Hamilton, also a municipally owned affordable housing complex built in 1967. For the Ken Soble retrofit, which yielded a 94-per-cent reduction in greenhouse gas emissions, the project included recladding the entire building with a noncombustible exterior insulation system developed by DuROCK, a Vaughan firm.
In both cases, they urged their clients to spend the money to actually overshoot building code fire safety requirements by using insulation products that offered effectively zero combustibility – a professional judgment informed directly by the Grenfell Tower catastrophe in London, in which 72 tenants in a low-income high-rise died when a kitchen fire end up igniting the building’s recently installed exterior aluminum cladding, creating a deadly inferno.
As it happened, they were both in London at the time. “It was a very intense moment,” Mr. Stewart recalls. “We ended up giving a presentation about our tower renewal work to, of all people, like the London Fire Marshal, who had just come back from that situation.”
The inquiry examining the causes of the Grenfell disaster issued its second, voluminous report earlier this month. The findings are exhaustive and go well beyond the problems with the flammable cladding material, and includes harsh critiques of an unaccountable building code inspection system, untested marketing claims by building materials producers and a municipal council, serving one of London’s wealthiest boroughs, unwilling to properly ensure tenant safety in a public housing project.
The findings “resonate in Canada,” says Jonathan Bisson, a Quebec City architect and the current president of the Royal Architectural Institute of Canada, adding that one of the Grenfell inquiry findings was that there were too many agencies involved in managing such projects, with the result that no one was ultimately in charge.
Evaluations of Canada’s building safety system conducted after the fire found that Canadian safety codes don’t permit the use of the cladding that ignited on the Grenfell tower, nor do our various systems – building codes, municipal inspections, et cetera – seem susceptible to the kind of self-dealing and negligence that contributed greatly to the U.K. tragedy.
A special committee established by the Canadian Board for Harmonized Construction Codes (CBHCC) “concluded that the National Model Codes generally provide sufficient provisions to prevent a fire event similar to what occurred at the Grenfell Tower,” according to a statement provided to The Globe and Mail. “With the release of the Phase 2 report of the public inquiry, the code development groups are planning to review the Phase 2 report and report back to the CBHCC in the near future, including any considerations for future code development.”
Yet not everyone is feeling entirely sanguine about Canada’s building safety systems. Ken McMullen, chief of Red Deer Emergency Services and president of the Canadian Association of Fire Chiefs, says his group has been pushing the federal government for a decade to establish a national fire administration office, specifically to harmonize fire safety standards across the country as a means of addressing lingering issues such as the safe storage of lithium ion batteries, which can catch fire or explode under certain conditions.
Mr. McMullen says his group is concerned that in the push by Canadian governments at all levels to accelerate housing construction or adopt new approaches, such as the development of multistorey dwellings with single-stair access, safety will be compromised. “These shouldn’t be after the fact type conversations,” he says. “We don’t want to look at Grenfell or other reports and say, ‘Gosh, I sure wish our government had heeded the advice of professionals like myself and the association that have said there’s things we need to do.’”
Some point to other sources of building safety risk. Ted Kesik, a professor of engineering at the University of Toronto and a building code expert, points to the impact of the long-term downward pressure on architects’ fees paid by developers.
In the way that structural engineers certify the integrity of projects such as bridges, architects assume legal responsibility for the safety of all the building materials used in a project – something that did not happen with the Grenfell retrofit. “Over the years,” Prof. Kesik says of the Canadian building sector, “developers have chiselled away at their fee structures, to the point where they’re not getting enough money to be able to do their jobs well.”
Fire isn’t the only human safety issue, he adds. As buildings become more airtight to prevent energy leaks, there’s an increased risk of toxic mould buildup due to inadequate ventilation. “Grenfell was truly a tragedy,” Prof. Kesik observes. “It won’t be quite like that here, because we have fairly good safety requirements with respect to the building enclosures. But that doesn’t mean that people will not be really seriously affected in terms of health and comfort and so on.”
In the case of both St. Hilda’s and Ken Soble, Mr. Stewart and Ms Santopinto persuaded their clients to go beyond the building code’s minimum standards in order to hit multiple goals – improved energy efficiency (which translates into lower operating costs), more robust fire safety systems, such as the deployment of sprinkler systems throughout, and the use of a completely noncombustible insulation system. (Normally, building codes allow combustible plastic foam insulation for use in new high-rises that are fitted out with sprinklers.)
“The retrofit of aging housing is intended to make these places safer, better, higher quality places to live,” says Ms. Santopinto. While experts agree that Canada’s building codes do guarantee minimum standards for safety, it may be worth going beyond those provisions, especially on housing projects, such as St. Hilda’s, with vulnerable tenant populations.
“One thing we’ve been able to do on our projects is add sprinklering where it may not be a code requirement by the letter of the code,” she says. “But it is best practice.”
Retrofitting aging apartments without using combustible insulation
According to Andre Turrin, technical director of DuROCK Alfacing, a Vaughan, Ont.-based exterior insulation manufacturer, there’s an odd gap in Canada’s fire safety rules that can be seen as both a problem and an opportunity. Current building codes allow new buildings over three storeys to employ polystyrene-based exterior insulation, even though it is combustible, because of all the other fire safety requirements, such as sprinkler systems.
Yet two generations of postwar apartment buildings that will soon need to retrofit their exteriors can’t use this common insulation because they weren’t constructed with sprinklers. “We have now thousands of such buildings that are in need of retrofits because they’re either poorly insulated or not insulated at all,” he says, adding, “Plastic insulation is not an option.
In 2018, Mr. Turrin’s firm began developing a noncombustible alternative and then started working with ERA and its contractor the following year to use it in the retrofit of the Ken Soble Tower, which is owned by Hamilton Housing. Exterior insulation systems, explains Mr. Turrin, consist of two layers of acrylic surrounding a vapour barrier and an insulation layer. For Soble, his team decided to swap out the polystyrene insulation for Rockwool, which is made from quarried stone and is completely fireproof.
After exhaustive testing by the National Research Council’s building code committees, DuROCK’s new system was approved for use, and then installed atop the outside walls of the Ken Soble Tower. The new cladding is smooth and white, and stops the leakage of heat.
Every change in building codes creates new markets for building materials, and DuRock’s bespoke product is no exception, although Mr. Turrin allows that there’s been a limited take-up so far. At the moment, it’s about 50 per ent more expensive than the plastic system.
However, he’s not worried because the asset managers, non-profits and public agencies that own and operate the thousands of postwar apartment buildings across Canada will all get to the point where they can no longer put off those kinds of renovations.
“There’s going to be a huge demand once things take off,” Mr. Turrin predicts. “A lot of people are still sitting on the fence.”