Maintaining proper indoor air quality is important throughout the year, but especially so during winter. It is during winter when people tend to seal off their homes as much as possible from the outside environment, in order to keep a comfortable indoor temperature. This, unfortunately, also cuts off the flow of fresh air into the home, making the indoor air quality drop considerably. One of the most popular ways to deal with this kind of issue is to install a whole-house air filter in the home. However, there is one particular factor that you absolutely need to consider before installing a whole house air filter. Read on to find out what it is.
Air filters are essentially just fiber meshes that are stretched across a frame and inserted into the ducts. Air can still flow through the mesh, but any contaminants it carries will become snared in the fibers. The more closely the fiber mesh is woven, the smaller contaminants it can catch. This is where MERV comes in.
MERV stands for Minimum Efficiency Reporting Value. It’s a rating system that notes how tightly woven the air filter is, and therefore how many different kinds of contaminants it can capture. Low MERV air filters have more gaps, though they are still closely woven enough to capture “larger” contaminants like dust and pollen. Filters with a high MERV rating can be so tightly woven that they can capture individual virus and bacteria cells.
So, should you just install the highest MERV filter? No! Filters with very high MERV ratings require much more effort to push air through them. That’s no problem for larger systems, but residential forced air systems are often not up to the task. You should trust a professional to find the best air filter for you.