Home Air Filters: A Simple Buyer’s Guide

July 23, 2013

If you’ve ever wandered around the air filter aisle at a Wal-Mart, Lowe's or Home Depot with a confused look on your face, this buyer’s guide is for you.

We’ll give you the information you need shop for air filters so that you can be in and out of the store--fast--with the air filter that best fits your needs. 

Pick the right size

Make sure you get a filter that fits in your return vent.

To find the size you need, take out your current air filter from your return vent and look on the edges. You’ll see three numbers (E.G., 10 X 10 X 2). The first 2 numbers are the length and width of your air filter. These are the numbers you need to pay attention to when it come to making sure it will fit.

The third number is the thickness/depth. The thicker the filter, the more airborne particles it can catch.

Understand the MERV rating

MERV (Minimum Efficiency Reporting Value) measures how well an air filter can filter out air particles.  Higher MERV rated filters can catch smaller, more dangerous particles.

MERV ranges from 1-20, but honestly you’re not going to want anything over 12. MERV rated filter over 12 are more for hospitals. So unless you’re doing surgery in your home, anything above 12 is overkill.

Pick the type of air filter you want

There are a variety of types of air filters, so we’ll divide them into Basic, Better and Best categories based on their MERV rating.

Basic home air filters

The cheapest and most basic air filter are made of fiberglass. If you’re on a budget, these are the filters you want.

These have a MERV rating of 1-4, meaning they can catch only protect your heating and cooling equipment from larger particles, but they can’t improve you home’s indoor air quality. They also don’t last very long and need to be replaced every 30 days.

Better home air filters

Better filters are within the 5-8 MERV range . These last longer than their less expensive counterparts  and can improve your home’s indoor air quality by removing smaller, harmful airborne contaminants like:

  • mold spores
  • hair spray fumes
  • smaller dust particles
  • cat and dog dander

Two of the most popular air filters in this category are:

  • Pleated air filters – The pleats/folds allow for  a larger surface area and can therefore hold more pollutants.
  • Electrostatic filters – These have electromagnetically charged fibers so that they can attract very smaller indoor air particles. These also come in reusable/washable versions.

Best home air filters

These are the filters that are have a 9-12 MERV rating and can catch some of the smallest (as small as 1 micron) airborne pollutants.

A few air filters that fall in this category are:

  • Deep pleated air filters – These are just pleated air filters with that have a thickness/depth of 4 to 5 inches.
  • Electronic air cleaners/purifiers – This isn’t your typical air filter. These electronic air cleaners/purifiers are installed within your heating and cooling system and use

Need more information about air filters or air cleaners? Ask us for help online.