How often you should install new air filters might depend on the following:
- Air filter kind
- Overall indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the house
For basic 1"–3" air filters, manufacturers usually direct you to get new ones every 30–60 days. If you have from light to moderate allergies, you could install a better air filter or replace them even more frequently.
Or, if you live a more remote spot or less occupied home (like a vacation house) 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 home:
- Vacation home or single occupant and no pets or allergies: every 6–12 months
- Common suburban house without pets: every 90 days
- One dog or cat: every 60 days
- More than one pet or if anyone has allergies: 20–45 days