How regularly you should install new air filters may depend on the following:
- Air filter kind
- Complete indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the residence
For basic 1"–3" air filters, manufacturers usually direct you to replace them every 30–60 days. If you suffer from light to moderate allergies, you could upgrade the air filter or replace them even more frequently.
Or, if you reside a more country area or less occupied residence (like a vacation home) and there are a reduced number of cars around, annually may be regular enough.
Here are averages that may help you decide how frequently you should get a new air filter at your house:
- Vacation house or single occupant and no pets or allergies: every 6–12 months
- Common 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