It’s said by many experts that the air inside your home can be more polluted than the air outdoors. The effects of poor indoor air quality are undeniable, as recent studies have shown over the years. Headaches, dizziness and fatigue are some of the more immediate effects of poor IAQ, with long-term effects including the development of respiratory illnesses and even cancer, in some cases.
This is where HVAC filters come into play. A high-quality filter can help improve your home’s indoor air quality by removing a host of airborne pollutants, including pollen, pet dander, viruses and even certain bacteria. The following offers a quick guide on choosing 20x20x5 air filters for home use.
Alternative Part Numbers
Keep in mind that 20x20x5 AIRx filters are designed to replace a variety of filters made by well-known brand names. These include the following:
- Honeywell FC100A1011, FC200E1011, CF200A1024, FC35A1019, POPUP2020, 203721
- Accumulair DPFW20X20X5M13
- Flanders 82655.0452020, 82755.0452020
- Glasfloss HWP20204, HWP20204M13
- Purolator P25-3
- BestAir 5-2020-13
- National Filter Sales PF-03-202005HW-1
- Quality Filters SBHW11GQP
MERV Rating
To choose the best 20x20x5 air filter for your home, you’ll need to pick one based on its MERV rating. MERV ratings range from 1 to 16, with 16 being the highest possible rating for a residential air filter. The higher the MERV rating of a typical air filter, in most cases, the more particles it can trap.
It’s best to choose an air filter that offers the best performance for your home’s particular filtration needs. Filters rated at MERV 8 (Dust) offer the best overall performance when it comes to preventing dust buildup while MERV 11 (Allergy) air filters offer better performance at removing allergens, dust mites and spores. MERV 13 (Health) filters offer the best results for improving indoor air quality by targeting tobacco smoke and harmful airborne bacteria and viruses.
Filter Media
The overall effectiveness of an air filter usually depends on the media it’s made from. Our 20x20x5 filter features an electrostatically charged, 100-percent synthetic gradient media that not only captures dust and other airborne particles, but also resists microbiological growth. This media is encased inside of a moisture-resistant double-wall beverage board frame, supported by a sturdy grid made from 30-gauge galvanized metal.
Nominal Size vs. Actual Size
A 2×4 isn’t something you’d normally think about when choosing your next HVAC filter, but this classic lumber size has more in common with your filter than you’d realize. After all, a typical 2×4 isn’t exactly two inches by four inches, at least not in its final form. After its dried and processed into a usable product, the actual dimensions of a typical 2×4 are actually 1.5 inches by 3.5 inches.
The same goes for your 20x20x5 air filter. Upon purchasing one, you might notice that its actual dimensions (19 5/8-inches by 19 7/8-inches by 4 3/8-inches) may be a tad smaller than what’s listed. Despite the size listed on the filter itself (which is known as the “nominal size”), the actual size of your filter will be slightly smaller to accommodate the slot or cabinet it’s located in. Otherwise, you might have a hard time getting it to fit properly without damaging the frame or filtration media.
Shop all sizes and types of air filters and water filters on DiscountFilters.com.

