This Green House
The Gazette is taking a close look at how to improve your home to guard against climate change. Got a question on climate mitigation? Send it to [email protected] to be answered in a future column.
Global heating will bring longer, hotter summers to St. Albert, with the city’s climate adaptation plan projecting a near eight-fold jump in the number of 30-plus C days by the 2060s. That could bring with it more heat stroke, droughts, wildfires, and smoke — challenges we can address with some simple home improvements.
Keeping cool
“I don’t have air conditioning,” said Leigh Bond of St. Albert’s Boundless Renewables Consulting, so he turns to other, cheaper solutions.
One trick is to open a second-storey window and use a fan to blow air out of it, Bond said. Hot air rises, so this setup will spit hot air out of your upstairs so cold air gets sucked in downstairs. He recommended keeping windows closed during the day to keep out hot air and opening them at night when it is cooler.
Closing the blinds during the day can keep out the sun and heat, Bond noted. Cellular or honeycomb shades create insulating air pockets to keep heat in during the winter and block it out during the summer.
Better attic and wall insulation and triple-pane windows can all keep out the heat, reducing your need for air conditioning, Bond said. Mehmet Yigit says his Sturgeon County home stays a cool 17 C when it’s 32 C outside, in large part due to its excellent insulation.
Air conditioning systems can provide targeted cooling through portable units, Bond said. If you’re looking to replace your furnace, he recommended getting one with integrated air conditioning, as the added cost is often minimal. Air-source and ground-source heat pumps can heat and cool your homes and are many times more efficient than traditional systems.
Clearing the air
Forest fire smoke contains many harmful pollutants, such as particulate matter, nitrogen oxide, and ozone, said St. Albert air quality consultant David Spink.
“It’s just like smoking a cigarette,” he said, and it can cause heart attacks and other health conditions in vulnerable populations.
For the most part, Alberta homes are sealed enough to keep inside air separate from the outside, said Brian Fleck, a University of Alberta mechanical engineer who studies ventilation. By recirculating air through your furnace filter, you can screen smoke out of your home.
Fleck said you should aim to have a MERV-13 or better filter on your furnace and heat-recovery ventilator for best results, noting some older furnaces might not be able to handle such filters. Use weather stripping and caulking to seal air leaks elsewhere to stop smoke from infiltrating your home.
Spink said homeowners should keep windows closed when engulfed by wildfire smoke and use HEPA filters to catch most all particulates.
“There is no safe level of particulate exposure,” he said.
Pay attention to a filter’s clean air delivery rate rather than the number of particles it stops, Fleck said. A system that can clean a lot of air a little bit is better than one that cleans a little bit of air a lot.
If you don’t have a MERV-13-capable furnace or a portable air filter, consider a Corsi-Rosenthal box, which is basically a cube made from furnace filters, a fan, and tape.
Clean air advocate Amanda Hu said she started using these boxes in 2021 after wildfire smoke engulfed her Calgary home. She and other members of Fresh Air Schools Alberta now promote the boxes as ways to improve indoor air quality.
“I have one running all the time,” she said of the box, which keeps particulate matter levels in her home at near-zero levels.
A Corsi-Rosenthal box can cost less than $200 (assuming $40 for a fan and $25 per filter), Hu said. Most online designs (such as those available at cleanaircrew.org) suggest arranging the filters to create a cube, with some builders adding stylish or silly decorations to their boxes.
If it’s hot and smoky out, Hu said to tape a furnace filter over an open window, which she estimates stops about 65 per cent of particulate matter. Slap a fan on that filter alongside a Corsi-Rosenthal box, and you can get a clean, cool breeze going in your home.
For the outdoors, Hu, Spink, and Fleck all had the same solution: wear a mask, ideally an N95-rated one that fits snugly around your face.
