How regularly 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 typically instruct you to install new ones every 30–60 days. If you suffer from light to moderate allergies, you could get a better air filter or replace them even more often.
Or, if you're in a more rural area or less occupied house (like a vacation residence) and there are fewer cars around, every year could be often enough.
Here are averages that can help you decide how often you should get a new air filter at home:
- Vacation residence 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