Top 5 Best Washable Furnace Filters (2024 Review)

What Are Washable Furnace Air Filters?

Washable furnace filters are a special type of filter that can be cleaned periodically and reused — most of them can be used for several years or even the lifetime of your HVAC system (furnace and A/C).

And unlike disposable HVAC filters with cheap paper frames, washable air filters usually have some type of metal or strong extruded plastic frame.

With these strong frames, washable furnace filters usually last from 3-5 years with monthly cleaning, but some filters are rated for up to 10 years or even longer.

Synthetic Filter Media

Washable furnace filters are almost all made from synthetic materials as compared to the typical disposable filter that is made from cotton blends.

The most common synthetic filter media include polypropylene, polyester, and other types of synthetic fibers.

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How Do Reusable Air Filters Work?

Washable furnace air filters work very similar to disposable furnace air filters except that are made with synthetic filter media.

The synthetic filter media is usually made of polypropylene, polyester, or other types of synthetic fibers that filters dust but can be cleaned with water.

Regular paper and cotton filters just capture dust and debris but hold onto the dirt. If you tried to clean a normal paper filter with water, it would just break apart.

And similar to disposable filters, most of these reusable furnace filters have an electrostatic design which means that they capture dust and particles using static electricity. 

As air travels through the electrostatic air filter, the airflow charges the filter material which creates an electric charge, naturally attracting microscopic particles. There are also a few washable air filters that use nanofiber technology such as Filti instead of electrostatic charging.

Metal Framing

Washable air filters also tend to have much stronger frames than disposable filters.

The filter frame is usually steel, aluminum, or strong ABS plastic. Disposable filters have paper frames that can bend easily and only lasts for a month or two.

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What Are The Different Types of Washable HVAC Filters?

Washable air filters can be constructed in a variety of ways but probably the biggest difference will be in the MERV rating. 

The MERV rating will tell you how many particles the filter can capture, and washable air filters range from MERV 5 and all the way up to MERV 11 or greater. But just because the filter has a high MERV rating doesn't necessarily mean that it is better. 

If the MERV is too high, it may cause a pressure drop and damage your system.

Wide Range of Durability

Besides the MERV rating, reusable HVAC filters can have a wide range of durability and longevity. For example, if a reusable air filter has a metal screen on the front and back, this can give added strength to which another reusable air filter may be missing.

Pleating is also another difference among washable air filters. Pleats or ridges can add much more surface area to the filter which translates into more particulate capture and greater filtration.

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How To Pick The Best Reusable A/C Filter?

Choosing the best washable air filter is important if you want to get the full cost-saving benefits. If the washable filter is poorly designed, it may only last a year or two, and at worse—it can damage your HVAC system. Below are a few tips on selecting the top reusable furnace filters:

1. Selecting The Right Filter Size

This may seem like an obvious point, but you want to buy the right filter size for your system. You can pull out your existing disposable filter and look at the dimensions. Washable furnace filter manufacturers generally make a variety of different sizes, but they may not have your exact size.

It is also standard among filter manufacturers (washable or disposable) that they slightly undercut the filter, so you can expect the washable furnace filter to be slightly smaller than the stated dimensions.

If the filter doesn't fit snugly into the furnace, then it may rattle and make noise when the HVAC system is on. Air may also flow around the filter defeating the entire purpose of buying a washable filter.

If you feel that air is flowing around the permanent filter, you can try to get a tighter fit by using some type of rubber gasket or insulation such as what you would use for a door or window. I also recommend that you make sure that the slot cover is properly sealed.

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2. Choosing The MERV Rating

The main rating for HVAC filters is the MERV rating (minimum efficiency reporting value) which basically means how well the furnace traps particles.

The higher the MERV rating means that the filter is better at trapping particles (but also lessens the HVAC airflow).

There have been numerous studies that say residential homes should aim for a filter with a MERV rating from 7-13. A filter in the 7-8 MERV range is considered average, while 9-11 is high.

Just remember, studies have shown that MERV ratings higher than 13 in general do not outperform the lower MERV ratings—and may even damage your HVAC system by causing it to run harder.

It is important to make sure that your HVAC system can handle the MERV rating of your new washable furnace filter. If you buy too high of a MERV, then it may even damage your furnace because it will cause a pressure drop. 

Please consult your HVAC manual or specs for the stated maximum MERV rating or contact your HVAC contractor for advice.

3. Pleated Vs. Non-Pleated

Pleats are the ridges or folds within the filter media which gives it an accordion look to it. These folds give the filter more surface area and if you stretch out a pleated filter, it would be much longer than the actual size of the finished filter.

When a filter has more surface area, this means it will be better at catching particles.

This is why pleated washable filters are generally better than non-pleated filters, tend to cost more, and are more difficult to manufacture.

4. Metal Framing

When someone buys a washable filter, they want it to last a long time—even ten years or more. During my home inspections, coming across a warped or damaged filter is extremely common.

This is because disposable filters have a paper frame, which can easily bend when the force of the HVAC air flow is applied against it (especially if it isn't installed tightly).

If the filter doesn't last, then all of the potential savings over a disposable filter are never realized.

Reusable filters with rugged metal frames are definitely preferred over cheap plastic framing.

Read Also: How Often To Change A 1-Inch Furnace Filter?

5. Filters With Metal Screens

The airflow of an HVAC system can produce a significant amount of force on a filter.

Another way to add rigidity to a reusable A/C filter is by including a metal or mesh screen that sandwiches the filter media.

If you buy a washable furnace filter with a metal screen, this will help prevent it from bending or warping over the years.

High quality disposable filters also tend to have these gold mesh screens over the paper filter.

How To Clean Washable Air Filters?

The most common way to clean a washable filter is to take it outside, and spray it with a garden hose. If a hose is not practical such as during winter, you can also simply wash it under a kitchen or utility sink. You can read more details on my 5 steps to cleaning a washable air filter here.

It is important to use a soft bristle brush and to not damage the synthetic filter media.

If the filter is very dirty, it is a good idea to soak the filter in a bin with some mild dish detergent. After cleaning, you always want the filter to air dry before reinstalling into the furnace.

It is important to install the reusable furnace filter with the arrow on the filter in the direction of the airflow just like you would do with a disposable filter. If there isn't an arrow, then you can install the filter in any direction.

Our Reviews of the Best Washable A/C Filters

Here are my top picks of the best washable furnace filters and all of their pros and cons: