Maintaining a comfortable indoor temperature in your home isn't a matter of eliminating an annoyance; it's critical to prevent heat-related illness that risks your safety. This article summarizes a few points to consider more carefully when you're thinking about the upcoming extended period of hot weather (link to CBC) and how you'll cope with it.
Your House May Be Dangerously Warm
Both older people and young children are more susceptible to heat-related issues such as heat exhaustion, so it's critical that your home's indoor temperature stays below 30°C. During the 2021 heat dome, the high overnight temperature made "night flushing" ineffective. Night flushing refers to taking advantage of lower nighttime temperature by leaving windows open overnight to "flush out" the warm air inside and cool down the home's contents. However, if it's warm outside, there is little cooling effect.
British Columbia doesn't yet suffer temperatures as high as those that have recently created unbearable conditions in Louisiana and Texas (link to USA Today), or shut down cities in Iran (link to Reuters) and the local hot weather is causing so far only large wildfires and minor drought conditions (link to Grist). Nonetheless, heat can build up indoors over the course of a few days to raise the temperature above 30°C. Depending on the relative humidity, this starts to be a hazardous situation in which your body may not be able to cool itself off properly; remaining in this state could lead to heatstroke - a lethal condition. Heatstroke will more easily hit seniors and young children, but it can happen to people of any age.
The Solution to Cool Down Your Home
Here are three things that you can do to your existing house or which you can incorporate into the design of your new house that will result in a cooler indoor environment:
#1 Exterior shading devices or shutters
Traditional exterior shutters are effective at keeping the heat out, and other shading devices such as brise-soleils directly above the windows or deep roof overhangs prevent excessive sunlight from heating the indoors. Curtains, drapes, roller shades, and blinds all suffer from the fact that once the heat energy from either the sun or the outdoor air has passed through the glass to the indoors, most of it is trapped. This trapped heat builds up and raises the temperature. Shutters keep the heat mostly out, but they also rob you of your view and can make your house seem dark.
#2 Additional insulation
Virtually every Canadian understands that adding thermal insulation to the walls and roof of a house will help keep more heat inside. However, you may not really understand that adding thermal insulation to the walls and roof also helps keep unwanted heat OUTSIDE. It's exactly the same principle.
#3 Airtightness
Radiant energy from the sun or conductive heat transfer from the outdoor air are both significant factors in an unhealthy buildup of heat in your house, but the flow of air also carries a significant amount of heat. In the same way that a refrigerator with a gasket that doesn't seal properly will be less able to keep the food inside adequately cooled, leaks in the walls and roof of your house will let warm air from the outdoors inside. These numerous, tiny gaps and cracks simultaneously leak cooled air created by your air conditioning system and are the first thing that some air conditioning installers suggest that you fix.
Since the beginning of my architectural career, my focus has been on the integrity and performance of the building envelope - the parts of the building that separate indoor space from the outdoors (namely the roof, walls, floor, doors, and windows). This separation is as important to keep hot weather out as to keep cold weather out.
My SAPPHR Strategy™ includes an analysis of your priorities and the technical aspects of your project to determine the performance requirements for your building envelope. The subsequent Deep Blue Design™ phase develops a form and "design" that - among other things - minimizes unwanted heat loss from or heat gain into your house. This approach works for remodels and major renovations as well as to new house build projects.
You could be sitting comfortably in your living room reading a book or watching the clouds slip across the sky when there's an Extreme Heat Emergency, or you could again be laying uncomfortably on the couch with a cold cloth on your forehead or exiled to the garage to find some relief.
If you're planning on building a new house or extensively renovating your existing house in the next year or so, you can reach out for a free 30-minute phone call to learn how to start developing a strategy for ensuring that your house remains cool during extended hot weather.