Maintaining good indoor air quality

Sep 2021

indoor air quality

Whether it’s a summer heat wave or a winter cold snap, we spend a lot of time inside our homes, and that makes indoor air quality important. Modern homes like Longwood’s are designed and built to maximize air quality, but everyday life causes the quality to deteriorate. Frying food, household cleaning, dander from our pets: they can all result in air that’s stale, smelly, even potentially harmful to people with allergies or respiratory illnesses like asthma.

Here are some tips on keeping your indoor air quality at its best.

Heating & cooling systems

Regular maintenance of furnaces, HRV (heat recovery ventilators), built-in humidifiers and air conditioners is essential for good indoor air quality. Maintenance includes scheduled replacement of filters where that’s appropriate and an annual furnace and air conditioner inspection by a professional. Check your homeowner’s manual for details on maintaining your heating and cooling systems.

Kitchen & bathroom fans

At least every six months, clean or replace the filter on your range hood and remove the cover from your bathroom ceiling fans so you can vacuum the dust that collects there. Check your owner’s manual for instructions on your range hood filter and watch this video on cleaning bathroom fans:

Rugs & carpets

They look great and make your home cosier, but rugs and carpets trap dust, pet hair, pollen and other particles that can diminish indoor air quality. Regular vacuuming, especially if the vacuum has a HEPA filter, and occasional shampooing or laundering help keep those annoying particles at bay. The same goes for your couches and other upholstered furniture.

Bedding & drapes

These items are also magnets to dust, pollen and other irritants. Washing them regularly in water that’s at least 55 C will eliminate most of those problems. Dust and allergen-proof pillow and mattress covers as well as allergen-proof box spring covers are also a good idea.


Today’s homes have well-balanced heating and cooling systems that help keep humidity at the right level. But showering, cooking and other activities can drive the level up and cause mould and even contribute to window condensation, especially in the winter when we keep our homes closed up. If you notice this happening, start by checking your heating and cooling system (your homeowner’s manual can probably show you what to do). Opening a window in the winter also helps by letting cold, dry air into your home. A dehumidifier in the basement may help as well.


Some indoor plants have a reputation for filtering toxins and improving air quality, but those attributes seem to be a myth. All plants convert the carbon dioxide we exhale into the oxygen that supports life, but the number of plants needed to make a significant difference to indoor air quality would be so high that there would be little room for the human occupants of the home. However, caring for house plants brings pleasure to many homeowners and plants’ greenery looks good in any room.

Helpful resources

For more handy tips, check the Canadian government website on managing indoor air quality or the comprehensive guide from the U.S. Consumer Product Safety Commission.