Choosing The Right Air Filter For Your Furnace

The Best Ways to Keep Air in Your Home Clean

One of the best ways to keep the air in your home clean is to use high-efficiency furnace filters (rated MERV 11 or higher) and to change them regularly.

While changing your filter 3-4 times a year is typically sufficient, you may need to change more frequently if you are in an area that has poor air quality – such as areas impacted by a wildfire. People with asthma and allergies may also find that they need to change their filters more frequently.

When your furnace air filter becomes too dirty, airflow is restricted and your HVAC system has to work extra hard to circulate air through your house. This could result in higher energy costs and an overworked HVAC system. In addition, changing your filter regularly can:

See the difference between a dirty (removed after Camp Fire wildfire) and clean filter below:

air filter

What to Look For in a New Furnace Filter

To filter the most particulates out of your indoor air, Hayward Score recommends buying high-quality furnace air filters. Depending on the manufacturer, look for the following ratings:

MERV Ratings

A MERV 11 filter or its equivalent will remove smoke particulates in addition to pet dander, mold spores, pollen, and household dust. A MERV 13 filter, or its equivalent, will also remove bacteria and virus carriers.

If you use furnace filters above MERV 13 or its equivalent, you should have a Heating/Cooling professional evaluate the efficiency of your system.

A Few Last Tips for Maintaining an Air Filter:

For more information on the importance of air filters, read our article on Breathing Well During Wildfires here or read the EPA’s Guide to Air Cleaners in the Home.


Hayward Score can help you discover what may be going on in your home in minutes! Simply answer a quick set of questions about your home developed by our healthy home experts, then get a personalized list of action items designed to help you address issues in your home. Start transforming your home today! Get your Hayward Score now.

Getting to a healthy home can seem daunting, but it is possible and our experts are here to help! You can Ask an Expert, and one of our Hayward Score team members will contact you within 2 working days to schedule your call.

How useful was this post?

Click on a star to rate it!

Average rating 4.9 / 5. Vote count: 13

No votes so far! Be the first to rate this post.

Ready to Improve the Health of your Home?

Hayward Score helps you discover how your home may be impacting your health in minutes – – for FREE!

Answer a quick set of questions then get a personalized list of action items. Transform your home and health today!

Avatar photo
Joe Medosch
Hayward Score Healthy Building Scientist Joe Medosch has almost 30 years of experience as a contractor and 10 years as a master trainer with expertise in home performance, particularly in health and energy-efficiency. His proficiency includes building science & diagnostics and Indoor Air Quality (IAQ) assessments. He has served on numerous committees developing industry standards including: RESNET Standard 380, Equipment Sub-Committee, and BPI multifamily standards development.
Related Articles


Our guide on indoor quality will help you diagnose possible issues and implement intelligent solutions to improve the quality of the air inside your home.

Related Articles