How regularly you should change your air filters could depend on the following:
- Air filter type
- Total indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the home
For basic 1"–3" air filters, manufacturers typically direct you to get new ones every 30–60 days. If you suffer from light to moderate allergies, you could install a better air filter or replace them even more frequently.
Or, if you reside a more country spot or less occupied residence (like a vacation residence) and there are not as many cars around, each year might be regular enough.
Here are averages that may help you figure out how frequently you should replace the air filter at home:
- Vacation home or lone occupant and no pets or allergies: every 6–12 months
- Average suburban residence without pets: every 90 days
- One dog or cat: every 60 days
- More than one pet or if anyone has allergies: 20–45 days