You Might Not Be Replacing Your Home’s Air Filters Enough, Experts Warn

Keep the air in your home clean and your HVAC system working efficiently with these expert-approved tips.

When was the last time you replaced the air filters in your home? With poor air quality becoming a growing concern across the United States and Canada, you are probably more aware of your home’s air filters than ever before. Air filters help keep our home’s air clean and free of dust, dander, and pollutants. This not only helps us breathe easier, but it also keeps the HVAC systems in good shape and prevents them from experiencing potential damage due to the buildup of airborne particulates.

Whether you use a standalone air purifier or rely on the filters in your home’s central HVAC system, replacing the filters on a regular basis is essential. So, how often should you replace your home’s air filters, and do bouts of poor air quality affect how often the filters need to be changed? Here’s what you need to know about replacing air filters at home, according to HVAC experts.

Several factors affect how often you should replace the air filters in your home, including the type of filter you have, whether you are using an air purifier, and whether you have pets in the home.

“Typically, it’s recommended that you replace your air filters every 90 days for an average single-family home. If you have pets or suffer from allergies, you might want to do it more frequently—say, every 60 days,” says Josh Mitchell, HVAC technician and owner of Air Conditioner Lab.

Be sure to research the type of air filters you have and how often they need to be replaced. For example, fiberglass air filters usually need to be replaced once every 30 days, while pleated air filters need to be replaced once every 90 days. Portable air purifiers usually have filters that last a bit longer, such as HEPA filters that only need to be replaced once every six to 12 months or carbon filters that last up to six months.

Regardless of the type of air filter you have, it’s important to take a look at the filter every couple of months to see if it’s beginning to look clogged. Lifestyle and environmental factors in the home can affect the longevity of the filters, so it’s a good idea to get familiar with how often the filters can last in your home specifically.

So how does poor outdoor air quality affect your home’s air filters? For the most part, short periods of poor air quality probably won’t have much of an effect on the life of the filters. However, if your area experiences several weeks of poor air quality due to wildfire smoke, smog, or some other kind of pollution, you should consider replacing your filters more often, says Glenn Wiseman, RASDT, RHDT, and Sales Manager at Top Hat Home Comfort Services, based in Ottawa.

“Your HVAC filter will have to be replaced more often if your location struggles with poor outdoor air quality for prolonged periods. When the air filter becomes blocked more quickly, the HVAC system begins to run harder to overcompensate, which can waste energy and end up costing you more,” says Wiseman. In this case, changing the filter once a month instead of once every three months is recommended.

“You can also set your HVAC system to recirculate mode to temporarily prevent outdoor air from running through the system. Doing this will help the air filter stay cleaner and keep your HVAC system running better in the meantime,” Wiseman adds.