Are you wondering what the most common air filter sizes are? If so, you're in the right place. In this article, we'll provide a comprehensive guide to air filter sizes, including how to measure them and what the nominal size means. When it comes to air filters, the most common sizes are 20 x 20 x 1, 16 x 25 x 1, 20 x 25 x 1, 20 x 25 x 4, 16 x 20 x 1, 16 x 25 x 4, 20 x 30 x 1 and 12 x 12 x 1.To measure the length and width (L x W) of your filter, start by taking the smallest measurement first if it's not square. It's important to note that the actual size of a filter may be different from the nominal size (the size on the label).
This is why it can be difficult to find the right size of air filter at a local home improvement store. The best way to determine the size you need is to measure the filter that's already there, assuming it's the right size. Improperly sized or installed governable filter frames can cause air leaks, which significantly decreases filter effectiveness.
What Does The Nominal Size Mean?The actual size refers to the exact measurements of your air filter and the actual dimensions when you measure length, width and depth (thickness).
The nominal size is a rounded number that varies by brand. This is why many filters have part numbers for each brand they are compatible with. When it comes to air quality, newer system air filters don't just focus on protecting equipment but on improving the air quality in your home. This is why it's important to choose the right MERV rating for your family. You can also proactively clean the air and surfaces in your home by adding an air purifier in the duct that creates supercharged particles. Now that you know more about air filter sizes, you can buy your air filter with confidence.