With a myriad of products on the market, of all different varieties and qualities, you may wonder what type of air filters to buy. There is a difference in quality, and it is important you know what you are paying for in your purchase of air filters. The MERV (Minimum Efficiency Reporting Value) rating will give you a good idea of how effective the filter will be at trapping particles in your air. The lower the MERV rating, the lower efficiency of the filter and the more often it will need to be replaced. Hopefully, we can help you determine the needs of your family and home and narrow down for you what type of air filters to buy.
First, you should know that there are four types of air filters. There are fiberglass filters that are thin and have a simple surface to trap particles from the air. These filters were designed to protect your heating and cooling equipment, without much thought to air quality in your home. These filters are typically very cheap, but they only trap about 10% or less of the pollutants in the air of your home. The MERV rating on these filters usually ranges between 1 and 4. Pleated air filters remove more particles from the air in your home and have a MERV rating somewhere between 10 and 13. The more pleats per foot the filter has, the more particles will be removed, and they typically remove about 45% of the particles in the air. The third type of filter is the high efficiency filter. These filters remove up to 85% of the particles in the air of your home and have a MERV rating between 14 and 16. Obviously, these will be more expensive, but they can help control operating costs for your heating and cooling systems as well as provide much cleaner air for you and your family. Finally, there are HEPA (High Efficiency Particulate Air) filters. These filters can be used in a whole house filtration system or a stand-alone air purifier. They remove up to 98% of particles and have a MERV rating of 17-20.
When shopping for filters, you will likely see a micron rating, too. This rating tells you the approximate size of particle the filter is likely to attract. The fiberglass filters are best at trapping the larger particles, but not as efficient in trapping the smaller particles. The other types of filters are better at trapping the smaller particles, but larger particles, while they may be repelled, will likely settle on furniture rather than being trapped in the filter. Particles in the air typically range from 0.001 microns to 100 microns. Just for a little perspective, particles under 35 microns are not visible to the human eye, and particles under 5 microns are typically the most harmful to us.
In conclusion, we recommend a high-efficiency filters that has more than 10 pleats per foot and a MERV rating higher than 8. Knowing what type of air filters to buy can help you run your equipment more efficiently, save you operating costs, and most importantly, serve the health of your family better.