Skip to main content

Scott Stirrett is the founder and CEO of Venture for Canada and a 2022-23 Action Canada Fellow with the Public Policy Forum.

Canadians are dying from extreme heat. A British Columbia coroner’s panel found there were 619 heat-related deaths during the 2021 B.C. heat dome, with 98 per cent of the victims dying indoors, mostly in homes with inadequate cooling systems. Many more Canadians will die from extreme heat if action is not taken to protect the most vulnerable.

It is estimated that if greenhouse gas emissions continue to increase at the same rate, many Canadian cities will see at least four times as many days with temperatures above 30 C between 2051 and 2080 when compared with today.

Rising temperatures have significant public-health implications. For example, prolonged exposure to extreme heat can lead to dehydration, fatigue and a spectrum of heat-related illnesses (HRI), including heat stroke. By mid-century, the cost of HRI in Canada will likely be more than $3 billion a year.

Exposure to extreme heat also has significant negative repercussions on Canadians’ labour productivity and economic competitiveness. A study from the Atlantic Council observes that “workers in hot conditions are more prone to mistakes and reduced decision-making capacity, which can have impacts as minor as needing to redraft a document or as severe as causing injury or death.”

In the paper Heat-proofing Community Housing, which I co-authored with Aliza Moledina, Émily Soulières, Jessie Gill, Leslie Muñoz and Trevor Tessier, we found that extreme heat is increasingly prevalent in many areas of Canada, significantly impacting the suitability and livability of our housing.

Policy makers should guarantee all Canadians have the right to indoor cooling, which is not synonymous with access to air conditioning, through updating building codes to establish a maximum indoor air temperature, incentivizing the retrofit of buildings and encouraging urban design practices that mitigate the urban heat island effect.

Mandating mechanical air cooling for new builds, which includes air conditioning and heat pumps, as the City of Vancouver did last year for new multifamily homes, is an alluring quick fix to the extreme heat problem that unfortunately creates many new challenges. Air conditioning can exacerbate climate change through increasing energy use, make people sick by minimizing access to fresh air and natural light, and create a significant ongoing financial burden.

Instead, policy makers should consider mechanical air cooling as one of many tools at their disposal. In the most extreme situations, such as when temperatures soar to more than 40 C, mechanical cooling is the most effective way to protect Canadians from extreme heat. Nevertheless, there are other interventions, which are often less expensive and better for the environment than mechanical air cooling.

Adjusting building codes to create a maximum indoor air temperature will protect Canadians from the impact of extreme heat. The devil is in the details, and policy makers should be wary of not setting the mandatory indoor air temperature too low or too high. Certain buildings, such as long-term care homes or child-care centres, should have lower mandatory indoor air temperatures because of the increased vulnerability of their residents to extreme heat.

Like mechanical air cooling, adjusting building codes to establish a maximum indoor air temperature is insufficient in and of itself. Andrew Pape-Salmon, an adjunct professor of civil engineering at the University of Victoria, says that “the challenge with the building code is that it really only touches somewhere on the order of 4 to 6 per cent of the building stock in any particular year,” since it only affects new builds.

That is why incentive programs are also needed to encourage property owners to conduct retrofits that provide access to cooling. Heat pumps, which can provide access to both heating and cooling, can be an energy-efficient solution to protect folks from extreme heat. Passive cooling, which incorporates design and technology to cool a building without the use of power, should also be encouraged. Examples of passive cooling techniques include increased insulation, effective window design and placement, improved nighttime ventilation and enhanced shading.

The urban heat island effect, which is when urban areas are warmer than surrounding rural regions, means those living in cities are particularly vulnerable to extreme heat. To make cities cooler, policy makers should establish local urban tree canopy cover goals, prioritize the installation of a variety of green infrastructure and ensure a range of land uses in neighbourhoods.

Extreme heat is a silent killer and arguably the most significant threat from climate change. Policy makers must act by ensuring that all Canadians have access to adequate cooling in their homes.

Doing so will save lives and protect Canadians from a warming world.