How frequently you should install new air filters might depend on the following:
- Air filter model
- Complete indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the home
For basic 1"–3" air filters, manufacturers usually direct you to replace them every 30–60 days. If you have from light to moderate allergies, you could get a better air filter or replace them even more often.
Or, if you live a more remote area or less occupied residence (like a vacation home) and there are fewer cars around, each year might be regular enough.
Here are averages that might help you decide how regularly you should change the air filter at your house:
- Vacation home or one occupant and no pets or allergies: every 6–12 months
- Ordinary 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