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