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  4. Big vs. Small Spaces: What Size Means for Filter Selection
  • Filter Selection: Does Size Matter?

    Home size, room size and HVAC slot size will impact the amount and type of filters you’ll need.

    • It may sound strange, but size has many implications for air filters. The size of your home, size of individual rooms and size of your HVAC filter slot can all come into play when it comes time to buy new air filters. Let’s break it down through some common questions:

      What is the best air filter for my home?

      The best air filter for your home’s heating and cooling system will depend on a variety of factors, including the size of your filter slot and the types of particles you prefer to capture. For instance, our easy-to-manage Filtrete™ Smart Filters are among the best at capturing lint, dust, mold spores, pollen and pet dander, but the line is only available in the most popular sizes.

      Similarly, the right Filtrete™ Room Air Purifier Filter will depend on room size and your air cleaning needs. Small rooms (up to 110 square feet) can accommodate our small room air purifier devices, with our largest—our extra large room air purifier—working in spaces up to 370 square feet.

      How many air filters does a house have?

      No two houses are the same. Some larger, newer homes require two or more central HVAC units to effectively cool them. Some homeowners prefer to have two smaller units to assist with energy efficiency. Both of these scenarios require multiple air filters.

      Another scenario? Your HVAC system utilizes an in-wall unit in each room. There may be an air filter behind each of the return air grills. In this case, your home may have up to five air filters.

      If you have many HVAC filters, keeping tabs on the life of those filters simultaneously is easier than ever with the Filtrete™ Smart App. You can add multiple filters at home—or even at a second location (vacation home, anyone?)—as well as a compatible indoor air quality monitor.

      What size air filter do I need?

      Home air filter sizes must be known in order to purchase replacements. Filtrete™ Filter dimensions (height x width x depth) are printed on each filter frame. Note: the longest side is the width based on typical positioning of the filter in an HVAC system. Standard filters are 1” thick and Deep Pleat filters are either 4”, 4” slim fit or 5”.

      We know filter size isn’t the easiest detail to remember, especially when there are so many options available. That’s why our change reminders include this information in notifications.