How frequently you should install new air filters could depend on the following:
- Air filter model
- Overall indoor air quality
- Number of pets
- Household size
- Air pollution levels and construction around the home
For basic 1"–3" air filters, manufacturers typically tell you to change them every 30–60 days. If you have from light to moderate allergies, you could upgrade the air filter or change them even more frequently.
Or, if you reside a more remote location or less occupied house (like a vacation home) and there are fewer cars around, each year could be often enough.
Here are averages that may help you know how regularly you should change the air filter at your house:
- Vacation residence 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