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 home
For basic 1"–3" air filters, manufacturers often tell you to get new ones every 30–60 days. If you deal with from light to moderate allergies, you could install a better air filter or get new ones even more regularly.
Or, if you're in a more remote area or less occupied residence (like a vacation house) and there are a reduced number of cars around, annually could be frequent enough.
Here are averages that can help you know how often you should change the air filter at your house:
- Vacation residence or single occupant and no pets or allergies: every 6–12 months
- Common suburban home without pets: every 90 days
- One dog or cat: every 60 days
- More than one pet or if anyone has allergies: 20–45 days