In your gut it feels like the wrong thing to do: like you’re letting your house bake all day in stale air. Keeping windows closed for much of the day takes some discipline. The better strategy, in my view, is to keep your windows closed to lock in the cool air and then, if necessary, use a fan to move the air around and make yourself feel cooler. In fact, while the breeze feels nice, you’re actually letting loads of hotter air into your home. Opening the window on a breezy warm day may make you feel like you’re cooling off your house, but it’s an illusion. This advertisement has not loaded yet, but your article continues below. Indeed, at many times when I’d normally have opened the windows to let in the breeze, I discovered the outside air was actually three or four degrees (Celsius) hotter than it was inside. To my surprise, I found that many times when the outside air felt cooler than the air inside, the reverse was actually the case - sometimes significantly so. To make sure I was getting a fair reading outside, I always made sure to put the thermometer in the shade and not on any particularly hot surface. I took a small portable digital thermometer and actually measured the temperature outside and then compared that to the temperature inside. But recently I tried a more scientific approach. In the past, I usually decided whether to keep the windows open or shut just based on feel: If it felt cooler outside than inside, I opened a window. The next issue of Sunrise presented by Vancouver Sun will soon be in your inbox. If you don't see it, please check your junk folder. Manage Print Subscription / Tax ReceiptĪ welcome email is on its way.

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Opening and closing windows