Retrofitting Toronto's High-Rise Condominiums
As Toronto’s climate warms, upgrading high-rise condominium building envelopes is a critical .
Updated April 2025
Prepared by Daniel Dempsey →
It's Getting Warmer.
Toronto's Condos Need Care.
Toronto’s climate is changing exponentially, and our housing infrastructure needs to be prepared.
The annual average temperature from 1971-2000 was 8.3C. Recent projections based on business-as-usual emissions scenarios speculate that this number will be 10.7C between 2021-2050, and 12.9C between 2051-2080. Annual mean temperatures are rising in Toronto, and the demand for cooling buildings is steadily surpassing heating demands in colder seasons that have come to define the way we build in the city. Not only does this necessitate a change for how we build in the future, but for how we repair and maintain the infrastructure we already have.
Beyond rising temperatures, climate change implies increasing frequency of severe weather events. Annual precipitation is expected to dramatically increase, and with water infiltration in buildings accounting for about one third of all lawsuits filed against architects in Ontario, it’s reasonable to assume that our buildings are not resilient enough to handle the challenges ahead.
Improving passive systems should be prioritized over improving active systems.
If you wanted to take a walk outside in the winter, you might put on a thick sweater or coat to keep in the heat your body produces. Buildings operate on a similar principle.The envelope of a building acts as a barrier between the inside and outside. The better the envelope, the better the building can keep the inside cool in warmer months, and warm in colder months. An effective building envelope also doesn’t demand your heating and cooling systems to work as hard they might if the envelope was operating poorly. You’ve probably experienced a situation in the winter or summer where your energy bills were higher than usual. This is because your mechanical systems are working extra hard to keep the inside of your building at a desirable temperature.
Throughout the 20th century, mechanical systems became a ubiquitous part of modern building construction, allowing the envelope to be built with lightweight, less-insulating materials. Glass buildings can be very attractive, and while there have been significant improvements in the performance of glazed envelope systems, they aren’t as effective as solid walls. Over the past 50 years, we’ve seen a considerable number of condominium buildings constructed in Toronto with largely glazed exteriors, and improving those buildings will be critical to meeting our future climate challenges.
High-rise condominium units account for upwards of 10% of Toronto’s total housing stock.
In the context of a national housing crisis, building more housing is critical, but our existing housing assets should not be allowed to fall into disrepair and potentially face demolition. For most other types of homeowners in the city, there are clear pathways to conduct renovations to their buildings, however the condominium model of ownership in Ontario is not so clear.
For condominium owners and boards to plan for a substantial renovation of their building, it’s important that they be informed of the benefits they might see for their investment, as well as the challenges that need to be addressed to successfully enact their goals.
This website is intended to serve as a primer for condominium owners and board members to navigate the challenges associated with enacting a substantial renovation to their building envelope.