By Joel Schlesinger
Few place can compare to Winnipeg for dramatic changes in weather.
Over the course of a typical year, this city’s temperatures will swing from a frigid -30 C in winter to a blazing hot 30 C in summer.
Those wild swings from icy cold to sizzling heat combined with heavy rain and snow loads can take a toll, especially on the materials used in the construction of roads and buildings.
Which brings us to Ray Hoemsen and his colleagues at the Centre for Applied Research in Sustainable Development, also known as CARSI. The centre was conceived as a grass roots idea by the School of Construction and Engineering Technologies at Red River College.
Located on the Notre Dame Campus of Red River College, CARSI is one of places in Canada where builders can test materials for building envelopes – the outer walls of a building – to see how they hold up to the forces of Mother Nature.
To that end, the facility features a huge walk-in environmental testing chamber. Large enough for a car, the chamber has a barn-style door and is divided into two compartments, each of which can be independently controlled. On any given day, Hoemsen and his crew can turn the thermostat in either compartment down to – 40 C or up to 40 C; wall assemblies can be placed in a common wall opening and tested against temperature and humidity differentials.
Yet the testing done in the chamber is just one of many activities taking place at CARSI. Since opening in 2007, the centre has become one of Manitoba’s testing facilities for leading-edge construction techniques and technologies. It is also the province’s first dedicated applied research centre at a college or polytechnic, and one of the first college projects to have received funding from the Manitoba Research and Innovation Fund, now administered by Research Manitoba. The Canada Foundation for Innovation and building industry members also invested in CARSI. “Without this support, we wouldn’t have CARSI,” says Hoemsen, Director of Applied Research & Commercialization at Red River College.
During its brief existence, CARSI has already had a huge impact on construction in Manitoba. In fact, it’s quite possible that Manitoba Hydro Place, the Crown Corporation’s office tower located on Portage Avenue near the MTS Centre, would not be one of most lauded and successful environmentally sustainable high-rise buildings in North America if not for CARSI.
That’s because one of CARSI’s original industry partners was Manitoba Hydro, and its first research project was Hydro’s downtown headquarters. In fact, the building that houses CARSI was specifically designed and constructed with a removable east wall to accommodate testing the innovative curtain wall technology used in Manitoba Hydro Place’s design.
“Basically, Manitoba Hydro was able to install a doublecurtain wall assembly in CARSI similar to the one used in the building downtown to test it for energy efficiency,” he
The Crown corporation also tested other elements of its building at CARSI, including the efficacy of modular office furniture, acoustic levels and environmentally friendly
finishes (paint, carpet, etc.).
In addition to being a testing ground for the province’s construction industry when working on large projects, CARSI is also helping to set new standards for building energy efficiency and sustainability. In particular, CARSI has earned a reputation throughout Western Canada for its applied research regarding the testing of building envelopes of existing large buildings and the potential impacts on energy efficiency.
‘“Build tight; ventilate right’ is the saying they use in the industry for building envelopes,”
says Rob Spewak, Research Manager of Applied Research & Commercialization at
Red River College.
Funded by Natural Sciences and Engineering Research Council of Canada – or NSERC for
short – CARSI’s building envelope testing unit specializes in an often overlooked area
that can impact energy efficiency: whole building air leakage characteristics of large
institutional and commercial buildings, including multi-unit residential buildings.
Spewak and students from Red River’s Architectural/Engineering and Mechanical
Engineering Technology Departments have tested buildings across the province for air
leakage in building envelopes.
However, this is not just a matter of testing how airtight a building is; of equal importance
is where the air leakage locations are within a building. A building’s materials and assemblies
integrity can be impacted on the whole depending on the location of a given leak.
“With stack effect, in a building, warm air rises and there’s higher pressure at the top
of the building combined with mechanical systems pressurization and wind,” says Spewak.
“Warm, moist air can seep into cracks and other openings – any imperfection – and it can
eventually cause condensation to form within the wall assemblies, which can result in mould
growth, corrosion and freeze/thaw cycling, which will expand the water to push the walls
apart, leading to building envelope failure.”
Examples of envelope failure are numerous in Winnipeg, which has a large stock old buildings
built long before controlling air flow and humidity was a design consideration.
Spewak says the former Public Safety Building, the Winnipeg Convention Centre, Concert Hall
and even the Winnipeg Art Gallery are four well-known examples of building envelope
failure which all required costly repairs and retrofits.
Until CARSI launched its testing project, no mechanism existed for whole building air
tightness testing for large building envelopes in Winnipeg, though Manitoba Hydro had done
extensive testing on homes and some work on two large buildings.
Yet the need for this kind of testing to assess the impacts on energy efficiency was
compelling from a cost perspective. In light of this, Manitoba Hydro provided additional
funding to undertake this research in order to gain an understanding of the types of
energy savings that could be realized from constructing airtight buildings and performing
remedial sealing work for retrofit projects.
The benefits of CARSI to the economy of Manitoba are evident. Thanks to research at
CARSI, more than two dozen large structures have been tested so far, and the research unit
has developed the expertise to help establish new Canadian and even North American
testing protocols and standards for building envelope testing.
This research has complemented other activities at CARSI, such as the monitoring
of both existing and new building envelope materials with embedded sensors that monitor
the ongoing performance and stability of building envelopes.
CARSI’s first work in this area involved the restoration of the old Union Bank Tower in the
Exchange District when it was being retrofitted to house Red River’s culinary school, the
Paterson GlobalFoods Institute.
“The challenge was the building had been there for about 100 years with no insulation
and now we were adding insulation as part of the new design,” Spewak says.
Realizing the potential problems that might arise due to potential moisture accumulation,
architects and engineers working on the project worked with CARSI to install sensors
into the building’s exterior wall section to facilitate long-term monitoring of moisture
and temperature profiles.
Yet beyond helping the construction industry build more sustainably, CARSI has served
an equally important purpose by providing cutting-edge training for Red River students,
“We’ve been helping prepare our graduates for the workforce with the latest skills, using the
best new applied technologies that will help them forge long, successful careers.”
Want to learn more about Buildings Research at Red River College? Check out these videos:
Centre for Building Envelope Commissioning
The Centre for Building Envelope Performance (CBEP) is being established with the support of a $1.75-million grant from the Natural Sciences and Engineering Research Council of Canada (NSERC). This video shares the genesis of what led to the creation of this new Centre and gives a glimpse as to what Manitoba’s construction sector can expect to see in the future.
The Sustainable Infrastructure Technologies Research Group (SITRG)
Over the last five years, SITRG has been assisting local businesses in conducting applied research towards enhancing the performance of large commercial and institutional buildings, while engaging RRC faculty, staff, and students in the process. Hear about it from a few of our partners in the video (produced with the support of NSERC):