What the MERV?

If you are checking out this article, there is a good chance you need to purchase an air filter and are trying to make sense of all the options that are available. There are many types of filters in the market to choose from, but which one is right for you and your home?

There are many factors to consider when purchasing filters. Usually, when choosing filters you are choosing between cost and filtration ability. Quite often, more expensive filters exhibit more complex construction and can capture finer dust particles, allergens, and other pollutants.

Inexpensive filters perform less particulate filtration and are generally designed for the protection of your HVAC system. As you move up the product line to more expensive filters, you will find they attempt to perform two key roles:

Protecting your HVAC

Removing dust, allergens, and other particulates from the air.
Filters are rated according to which particulate they can capture and their dust holding capacity. Now here is where things get more difficult for the consumer. There are multiple rating systems for filters!

For understanding filter differences for this article, we will be following the MERV rating system that has been predominant in the market for the last 30 years. All other rating systems will have some variations on determining purpose & performance.

MERV stands for Minimum Efficiency Reporting Value. The MERV rating of a filter indicates the minimum particle size that can be filtered. Home filters fall between the range of 1 to 16 on the MERV scale. As the number increases, the filter can remove finer particulate from the air. This table outlines what each level of the filter can capture:

 

MERV Rating Chart

 

Give Me the Best!

Now, it would be very common to just assume that you want the highest rated filter, right? Not exactly. As the rating climbs, so does the filter price. Another side effect of higher rated MERV filters is that they tend to more restrictive to air flow and increase the stress on your HVAC system than a lower MERV filter. This can result in a higher energy bill because the HVAC must work harder to move the air through your home.

 

Your Recommended Filter

The best thing you can do is choose the filter that is right for you and your home based on your environment and personal judgment.

If saving money is the most important thing to you, choose a filter with a lower MERV. You will save money on both filter cost and total energy cost.

If you own pets, smoke, live in a smog heavy area, or are sensitive to airborne allergens – you may stand to benefit the most by using a higher MERV filter.

 

 

Conclusion

There is a range of options to choose from when selecting a home filter. The good news is that you cannot make a wrong selection. The most important thing you can do is ensure that you change your filters when they are full and clogged. Filters expire over time and will lose their ability to filter contaminants. A clogged filter will be unable to filter contaminants from the air and will increase system stress which will ultimately lead to higher energy bills and increase the likelihood for repairs.