RC107 JulyAugust2023 - Magazine - Page 20
BUILDINGS
“The biggest learning curve was the attention to detail and quality control that was
above and beyond anything else we’ve done
before,” Faustini says. “Maybe we’ve done it,
for example, for laboratories or high-performance buildings, but in the case of Passive
House, especially with the envelope of the
building, all the emphasis, or most of the
emphasis, was on that.”
He says this type of construction required
attention to certain details
that normally would not
require the same attention.
“For example, the types
of screws that subcontractors were using to
fasten their brackets to the
building were scrutinized
like never before,’” Faustini
says. “We spent about six
months designing the details around the windows,
which is extremely unusual, just to get it
right and to minimize the energy loss. So, between the architects and the consultants and
the manufacturers, we spent an enormous
amount of time just on that one detail.”
The windows for the project were pre-certified to the Passive House standard by the
manufacturers and sourced from the United
States after being vetted for thermal performance. Close to 800 triple-glazed windows
were pre-tested in the factory before being
shipped to site and then re-tested on site to
validate compliance.
He says Pomerleau erred on the side of
extreme caution when constructing and
designing the residence.
“Certain things were not absolutely
necessary but needed to be done to create a
buffer to make sure that we weren’t getting
too close to the compliance limits,” Faustini
says. “Because we were working during the
pandemic, everything was still mostly virtual. So, we went back and forth several times
with documentation. The subcontractors
would submit documents of what they were
planning on doing, and then the Passive
House consultant would come back and
there would be markups all over the pages
in red. It was like getting an F on a test. To
address this, we built a full-scale mock-up of
the envelope onsite, so anytime there was a
question or concern, we had a physical model to quickly reference. It helped expedite the
review and approval period a lot.”
Another challenge for Pomerleau was
educating their teams and the various trades
on building and installing to Passive House
Standards.
“That was a huge component. And it was
a big risk, because if we didn’t get the certification, reputationally, that would’ve been
damaging. So, that was number one. Even if
COVID didn’t exist, that would’ve been the
major challenge,” Faustini says.
Adding to those challenges was navigating a world in the grip of a pandemic.
“With the COVID situation, we were dealing with major supply issues and material
delays, but we still managed,” Faustini says.
you’re cooling. It’s all being done through
fan cool units at the suites.”
Building sustainable relationships
For Pomerleau, working under the designbridge-build model removed some of the
uncertainty around building to Passive
House Standards.
“UTSC designed the project up to a certain
point to make sure all their stakeholders had
“[U of T] hopes that by producing a passive house residence at this scale,
developers will see the benefits of this type of construction.”
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RENEW CANADA – JULY/AUGUST 2023
“We’re going to essentially finish on time
despite having some challenges to overcome.
We started later because of city permits,
dealing with material supply challenges, and
union labour strikes last year.”
Passive House features
One of the most important features of a
Passive House building is the building
envelope.
“That’s probably the most important
thing because you must reduce the amount
of energy loss for the skin of the building.
And then in terms of energy efficiency, the
mechanical system is designed to recuperate
heat and recuperate energy. We have a pit in
the basement that uses the hot water from
the showers and uses that as a heat pump
source in the basement—same thing with the
kitchen exhaust. The heat from the kitchen,
the cooking at the commercial kitchen is
reused as much as possible to preheat some
of the exterior air,” Faustini says.
There are also energy recovery units installed on the roof of the residence.
“The distribution of heating and cooling
in the building is done locally, as opposed
to doing it at a centralized location on the
roof through the air handling units. It’s
preheated, but then most of the temperature
control happens at the suite by the students,”
Faustini says. “Depending on the location of
the suite, there might be certain temperature
demands. So essentially, you’re not paying
or consuming unnecessary heat if you were
to distribute the entire building at the same
temperature, for example, or at a general
temperature that there may be some cases where you’re heating, and then locally,
given the green light to say, ‘Okay, we know
what the layout is going to be. We know
the number of beds. We know the administrative spaces we need,’ et cetera,” Faustini
explains. “When they got the feedback from
their stakeholders completed, which normally happens later during the design progression stage of a design-build, that meant they
went far enough with the design to avoid
major program changes down the road.”
Having the design approved at this stage
reduced some of the risk for the bidders as
there was enough comfort that meeting Passive House Standards was possible.
“If [the University] would have forced Passive House on us with no design in place and
we had to design and build it from scratch,
we would have said there’s a tremendous
amount of uncertainty. So, they wanted to
bring it to a point where they felt that the risk
was minimized,” Faustini explains. “Once
they had brought it to that point, then they
wanted a turnkey solution and for Pomerleau
to take it from where it was, finish the design
and build it for them. And I think that was a
really good model for this new realm.”
While the first group of students are set
to move into the residence in September
2023, the partnership between the University
and Pomerleau will continue. The contractor was recently awarded another contract
by the university to construct a 14-storey,
above grade educational facility at Devonshire Place, south of Bloor Street in Toronto.
This building is expected to be the tallest
cross-laminated timber (CLT) and concrete
hybrid building in North America. The first
timber is to be delivered to the site in November 2023.
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