Humber College’s NX Building Receives Zero Carbon Building Design Certification by the CaGBC

Humber College’s retrofitted NX building has been awarded the Zero Carbon Building – Design Certification by the Canada Green Building Council. The NX building is Humber’s most energy efficient building, and the retrofit uses 70 per cent less energy than before. It’s the first retrofit in Canada to achieve zero carbon design certification, according to Canada Green Building.

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“Congratulations to Humber College for earning a Zero Carbon Building – Design certification for their NX building,” said Thomas Mueller, President and CEO of the Canada Green Building Council. “As the first retrofit to achieve zero carbon design certification, Humber College is showing real leadership and innovation in green building and carbon reduction. The NX building demonstrates that Canada has the expertise and technology now for buildings to reach zero carbon and contribute to global climate change efforts in a meaningful way.”

Transforming the NX building required a retrofit that is insulated and airtight. To achieve the thermal energy performance requirements of CaGBC’s new Zero Carbon Building Standard, the original aluminum curtain walls, spandrel panels, and a glass vestibule were replaced.

The new envelope retrofit features high-performance skin and engineered transitions for quality air control to mitigate thermal bridging. In addition, new super-performance windows were also installed for better energy efficiency.

An air-source Variable Refrigerant Flow-Heat recovery (VRF) system was selected to recover and transfer heat between zones, which exchanges heat with the ambient air instead of the plant’s water loop.

Two new air-cooled VRF heat pumps were installed on the fifth floor, and fan-coil units were installed for each thermal zone to keep the temperature consistent across the building. An electric radiant flooring system was installed as well to accommodate the colder winter months.

Lighting arrangements were upgraded with a new OSRAM Encelium lighting control system, which features sensors that communicate data.

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It’s estimated that the new photovoltaic (PV) system mounted to the roof will generate approximately 31,500 kWh per year. Any excess energy will be fed into the campus central plant, to be used by other buildings.

“Globally, buildings are responsible for 40 per cent of annual energy consumption and up to 30 per cent of all energy-related greenhouse gas emissions,” said Spencer Wood, Humber’s Director of Facilities Management. “One of the biggest challenges to reducing greenhouse gas emissions in Canada is finding ways to heat buildings at a reasonable cost without burning fossil fuels. Humber wanted to be an example to the Canadian design and construction industries on how a deep energy retrofit can contribute positively to our country’s climate.”

Designed by B+H architects and constructed by BIRD Construction, renovations to the NX building began in May 2018 and are scheduled for completion this summer.

As part of its energy plan, Humber is investing in energy efficient methodologies and new performance benchmarks, such as the Zero Carbon Building Standard, to reduce its GHG emissions to 30 percent by 2034.

“We’re immensely proud to be a strategic partner to Humber College in advancing its sustainability leadership within the postsecondary sector in Canada,” said Holly Jordan, Principal, B+H. “The NX Building exemplifies how, through careful integration across architectural design, energy modelling, envelope design, and mechanical and electrical design, guided by Humber’s unwavering Integrated Energy Master Plan vision, we can look to Canada’s postsecondary institutions as powerful catalysts for change that will continue to drive the green building industry forward.”