In Canada, many city bylaws require buildings to be heated during the winter months, and many utility companies are not allowed to turn off a home's heat in winter, even if a bill goes unpaid.

But there are no such bylaws in place to protect people when the temperature gets extremely hot.

As temperatures around the world climb, causing more frequent heat waves, some advocates suggest it's time to re-think how we handle hot temperatures.

And it's not just because hot weather can be uncomfortable — it can be deadly, particularly to the elderly and the homeless.

So why aren't the most vulnerable people in our society protected from life-threatening heat?

More record temperatures

Alan Hedge, a professor in the department of design and environmental analysis at Cornell University in Ithaca, New York, said heat can be more challenging to deal with than cold.

He said this is because there are very real limits to what a person can do when it's hot.

"If you're cold, you can put more clothes on and the more things you put around your body, the more you'll insulate your body. But if you're hot, you know, once you're completely naked, you can't do anything else," he said.

Hedge said Canadians are generally used to dealing with more cold days than hot, so our buildings are not designed to deal with the heat. And our cities have a lot of concrete, contributing to the "heat island effect" that makes cities hotter than rural areas.

Even though Canada tends to be thought of as a cold country, Health Canada expects the number of extremely hot days to double in many parts of the country in the coming years.

Many elderly people who live in public long-term care housing do not have air conditioning in their units and many units do not have windows that open. (Jean-Paul Pelissier/Reuters)

And cities across the country have seen a record number of hot days this summer.

Canadians should start thinking differently, said Hedge — air conditioning and forms of cooling should no longer be considered a luxury.

"We know that we're getting record temperatures, so we have to start to design environments that can keep us cooler when it's very hot."

Some long-term housing 'oppressively hot'

Tracy Heffernan, a lawyer at the Advocacy Centre for Tenants Ontario, said the mortality rate for homeless people is higher during a heat wave than during a cold snap.

Toronto, like many cities across the country, opens cooling centres in heat waves, but only one is open at night.

In heat waves,Toronto also extends the hours for several public pools, which are free to enter, from 8 p.m. until 11:45 p.m. While that certainly helps, it doesn't provide relief from the overnight heat.

This is a particular challenge for the homeless because Health Canada says that's when people are most at risk for heat-related illness or death.

People who live in public housing also face greater challenges during heat waves.

"They may not have money to buy a fan, and they may not have access to any air conditioning in their building — it's a really bad combination," she said.

Similarly, many long-term care homes for the elderly do not have air conditioning and unit windows do not open for safety reasons. This leaves some units "oppressively hot," said Jane Meadus, a lawyer with the Advocacy Centre for the Elderly.

Meadus said the only requirement in a long-term care home is that a portion of the building, usually the common room, must be kept cool.

Another group particularly hard-hit when it gets hot is the homeless. Many cities open cooling centres during a heat wave, but most are not open overnight. (The Canadian Press)

She said some people have family that can bring them a fan, but many are on their own and speaking up can be a challenge.

"It's where they live, and I think a lot of people, especially seniors who don't have a lot of support, feel very vulnerable, so they often won't say anything," said Meadus.

Some can't say anything, even if they want to, due to issues like dementia.

Worst-affected 'easy to ignore'

Even if more cooling centres were open longer, Heffernan said they're "just a stop-gap measure" and not a real solution.

Both Heffernan and Meadus said the government should institute a maximum temperature that buildings can reach, similar to how many cities have instituted minimum temperature requirements for buildings during winter.

"I'm not saying it has to be polar, but when you're having the kind of heat we've been having this summer, it's just terrible for some and it can be a real health risk," said Meadus.

The people most affected are already very marginalized, which means thinking about the impact of hot weather is a low priority for most legislators.

"These are populations that are quite easy to ignore," said Heffernan.

And they don't always have the resources they need, said John Argue, who is on the board of the Ontario Society of Senior Citizens' Organizations. He also worked for more than 10 years at a community legal clinic in Toronto.

"If extreme heat is a problem aggravated by the particular building — with bad air flow or no air conditioning or no air circulation — these tenants don't know where the heck they can go," he said.

The City of Hamilton is poised to shave a month off the time landlords must provide heat because climate change has made warm weather start sooner and last longer. (Chris Seto/CBC)

Some cities, like Hamilton, are considering changing their bylaws due to climate change. The city's temperature has increased by 2 C over the past 30 years, according to Environment Canada records. The city will soon decide whether to shorten the number of months that landlords are required to heat buildings in winter.

While that gives landlords a break, it doesn't do anything for residents who are feeling the heat during the summer.

Heffernan said cities need to build more affordable housing to help these vulnerable populations, and make housing smarter so that air can flow freely during hot summer days.

In the meantime, Heffernan said cities should mandate that cooling centres be open 24 hours a day in heat waves.