Fiberglass Air Filters vs. Pleated Air Filters

Learn the difference between these two types of air filters and which one's right for you

Homeowners don’t always know where to start when it’s time to choose an air filter. Because there are several types available at most stores, it’s easy to base your buying decision just on price alone. However, while the cheaper fiberglass air filter might seem like a smart idea for your budget, it may not always be the best choice for your home, your HVAC system, or your family’s health.

Fiberglass vs Pleated air filters

Things to Consider

To determine which is the best air filter for your home furnace or air conditioning unit, you'll need to consider a few key factors:

  • Price: How does the cost of the filter fit into your budget?
  • Frequency: How often do you need to replace it?
  • Quality: How well-made is the filter's construction? What materials are in it?
  • MERV rating: Will it trap all the particles you need to be filtered in your home or business?

Comparing the Two Most Common HVAC Filter Types

Fiberglass Air Filters

Pros

  • Inexpensive: You'll easily find fiberglass filters for a few dollars or less.
  • Catch larger debris: Lint and dust are captured easily by fiberglass.
  • Airflow: New fiberglass filters will not impede airflow. However, if you don't change your fiberglass air filter monthly, it may become clogged and impede airflow, which will create issues for your unit.

Cons

  • Frequency: Fiberglass air filters need to be replaced every 30 days.
  • Quality: An especially flimsy fiberglass filter can come apart in your system, causing serious damage, as well as putting any filtered debris back into the air.
  • Less filtering capability: Because they don't have a lot of surface area, they don't filter out smaller items like pollen, bacteria, and viruses. This makes them a poor choice for people who suffer from allergies, asthma, and other sensitivities.
  • Not recyclable: Fiberglass is not a recyclable material, and because you must replace fiberglass filters more often, you'll be sending more trash to the landfill.

Pleated Air Filters

Pros

  • Catch more debris: Pleated air filters have more surface area, so they capture more – and smaller – debris. Depending on the MERV rating, they may filter out pollen, pet dander, bacteria, and some viruses. This makes a pleated air filter a much better choice for anyone with allergies, asthma, or similar sensitivities.
  • Frequency: Pleated filters can last up to 90 days before they need to be replaced, depending on the time of year and the environment in your home or business.
  • Recyclable: Pleated air filters may be recyclable in your community. Check with your local authorities to confirm.

Con

  • Price: Pleated air filters may cost a little more – ranging from $5 to $15 – but they are a good example of getting what you pay for.

Frequently Asked Questions about Fiberglass and Pleated Air Filters

Are fiberglass air filters safe?

Yes, for the most part, fiberglass filters are safe. But they fall short compared to pleated filters when it comes to filtering out the smaller contaminants in your air such as pollen, pet dander, and bacteria. You should also be aware that, because they don't have a lot of surface area and don't filter smaller particles out, they eventually can cause build-up and weaken your HVAC system and decrease its efficiency, which may lead to higher energy costs.

What is a pleated filter?

A pleated filter is an air filter that is made from a pliable material – polyester, cotton, or paper – that is folded to look like an accordion and housed in a cardboard frame. The folds – or pleats – give the filter more surface area, which allows it to capture more particles.

What are pleated air filters made of?

Pleated filters can be made of paper, cotton, polyester, or other pliable materials. For example, the filter media in our MERV 13 pleated filters is made of polypropylene/acrylic fibers. This high-quality, synthetic, plastic-based material allows the filters to trap particles as small as lint, dust mites, mold spores, pollen, pet dander, fine dust, smoke, viruses, and bacteria.

Are pleated air filters better?

While fiberglass air filters will do the job in the most basic way, in most cases, pleated air filters are much better. They can filter out smaller particles – important for people with airborne sensitivities. They are less likely to clog in a short amount of time, and they can last up to 90 days. They're also recyclable in most communities, which makes them a good choice for the environmentally conscious.

My property manager says fiberglass is the only material my unit can handle. Why would that be true?

While we don't know the exact reason that your property manager would make that claim, our guess is that he's concerned about airflow through the building's ventilation system. Fiberglass filters, when changed regularly, do allow for more airflow because they have less surface area than pleated filters and allow the smaller particles to get through. However, if you don't change them every 30 days, you'll find they have the opposite effect by getting clogged and potentially harming your system.

If you're ready to find the right air filter for your furnace or air conditioning unit, you can search by filter size or by MERV rating.

If you're interested in learning more about caring for your system, check out our other Helpful Tips pages.