Are Thicker Air Filters Better for Your Home?

Most air filters are 1 inch thick, but some systems can accommodate filters 2 to 5 inches thick. In our tests, we found that the thicker the filter, the better it works and the longer the replacement intervals. This means it's better for you and your heating, ventilation and air conditioning (HVAC) system. Thick air filters may automatically seem like the best option. Thicker means more filtration, right? In most situations, that's the case.

Thicker air filters tend to last longer because they have more square feet to capture and retain air particles. To put it into perspective, a 1-inch air filter may need to be changed every month, while a 4-inch air filter can last up to six months. Virtually any HVAC professional will tell you that thicker filters perform better than common 1-inch oven filters. Thicker filters, known as media filters, are generally 4 to 5 inches thick compared to ubiquitous 1 inch filters that you can even buy at grocery stores. The short answer? A 4-inch filter will last longer and provide better air quality for your home.

Summary line? The thicker the filter, the more dirt it can hold. And, therefore, you can enjoy a wider range of filter frequency replacement. Therefore, the oven filter change time will be much longer. Replacing your standard one-inch air filter with a 5-inch pleated filter can improve the air quality inside your home. This is because larger air filters have higher MERV ratings, leading to better filtration of contaminants and allergens.

Oven filters designed to act as whole-house air filters add stress to the blower in an HVAC system by impeding airflow. Two design adjustments to the facility can resolve this problem and potentially prevent an after-hours call from a disgruntled customer. Reducing the thickness by one inch shouldn't be a big deal; for example, you should be able to use a 4-inch filter instead of a 5-inch filter. A 1-inch filter with less surface space will clog up fairly quickly and will need to be replaced much sooner than a coarser filter. Deeper depth can also improve filter life and efficiency; they also make it easier for air to enter and exit the filter. While you most likely know the size of filter your unit needs, you may not know what type of air filter is best for your home needs.

This method assigns numbers based on the expected level of efficiency at which a specific filter captures particles from the air as it passes through the filter. Now, air filters have adopted the use of this method, and more and more people are using specialized air filters with carbon. These 4-inch media filters can have 20-30 feet of surface area with their pleated (accordion) filter material. The same is true when homeowners replace installer-provided high-airflow filters with high-MERV restrictive filters. Most HVAC technicians recommend changing 1-inch air filters every 30 days, while 4-inch filters can be changed every 3-6 months.

These media filters have much stiffer cardboard frames, and some media filters even have plastic “rails” on the top and bottom so you can slide them inside the oven with a very tight seal. For comparison, a 4-inch thick filter will have approximately twice as many surface areas as a 2-inch thick filter. While some of the more expensive filters may advertise that you can use them for up to three months, these filters can be a burden on your system. The second option is to double the filter area by channeling a second filter to supply the blower from a second side of the unit or from below. If you put together several 1-inch filters, it's similar to putting together 5 coffee filters and trying to brew a cup of coffee, it just doesn't work. In conclusion, thicker air filters are generally better for your home than thinner ones because they provide better filtration of contaminants and allergens while lasting longer than thinner ones. They also make it easier for air to enter and exit the filter due to their deeper depth.

However, if you choose to use thicker air filters in your home, make sure that they don't add too much stress on your HVAC system by impeding airflow.