How frequently you need to replace the air filters could rely on the following:
- Air filter type
- Overall indoor air quality
- Quantity of pets
- Household size
- Air pollution levels and construction surrounding the residence
- Your MERV Rating
For standard 1"–3" air filters, brands usually tell you to swap them every 30–90 days. If someone in your family suffers from mild to moderate allergies, you can put in a better air filter or change them even more frequently.
The quick answer to "how frequently should I exchange the air filter?":
If there isn't a smoker or pets in the home, and your filter is the often sold 1" filter with a MERV rating of 4, you should be able to wait up to 90 days before replacing it.
What air filter brands last longer?
Many air filters are supposed to last up to six months, while others should be exchanged each month. The thicker the air filter, the longer it should last. Generally, you can check the thickness of the filter rather than the brand. You also need to consider at the MERV Rating.
The MERV Rating is a scale that stretches from 1-20 and measures how well an air filter can pull particles from the air. The higher the MERV Rating, the smaller the particle that will be captured by your air filter.
While a filter with a higher MERV Rating will last longer, it can also impede the circulation in your home. And you will need to replace the filter more regularly. And if you have an older piece of equipment, plan to replace the filter more frequently to extend the quality of your filter.
How frequently do I have to substitute my air filter based on thickness?
The longevity of an air filter also relies on its thickness. A 1" filter will need to be replaced more frequently instead of a 4" filter.
- A 1" pleated air filter should be exchanged every 30-60 days.
- A 2" pleated air filter ought to be switched every 3 months.
- A 3” pleated air filter must be switched every 4 months.
- A 4" pleated air filter must be changed out every 6 months.
- A 5” or 6" pleated air filter ought to be swapped every 9-12 months.
One of the perks of thicker filters is not only do they survive longer, but they also posses a higher MERV Rating. This means they can do a better job of getting rid of the particles within your home. They also produce less air resistance, which can help your HVAC system function more efficiently and cut down on strain on components including the blower motor.
If you have a whole-home air purifier, you will also have to exchange the filters more frequently.
How frequently should I exchange my air filter if I have a dog or cat?
If you want pets, you might have to change out your air filter more regularly. Pet hair and dander can easily clog an air filter and lower its effectiveness. For every shedding dog you own, expect to replace the filter a month earlier than you would with a home lacking pets. The same is true of cats, although they usually do not shed as often as dogs. If you have a hypoallergenic or non-shedding dog or cat, you might not need to switch out your air filter as frequently.
Although a good rule of thumb, you will need to examine your air filter more often to determine if it has to be exchanged. Dogs don't shed the same amount year-round. They shed more in the spring and fall when they are blowing their coat. Take a look at the air filter each month and exchange it when it appears clogged.
Here are averages that might help you know how often you should install a new air filter at your residence:
- Vacation house or one occupant and no pets or allergies: every 6–12 months
- Standard suburban home without pets: every 3 months
- One dog or cat: every 60 days
- More than one pet or if someone has allergies: 20–45 days