When it comes to choosing the right air filter for your home, it can be difficult to know which one is best. The American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) suggests the MERV 13, but this may not be the most efficient option for some residential HVAC systems. In fact, the MERV 11 may even be too restrictive. The MERV scale is used to measure the effectiveness of air filters in capturing particles.
The higher the filter rating, the smaller the particles it will capture and the higher the percentage of particles captured. Low-efficiency filters are generally found within the MERV 1-4 range, while high-efficiency filters are typically rated MERV 13 and higher. It's important to note that the MERV scale is not linear; the difference between a MERV 6 and a MERV 8 is almost double in terms of the percentage of particles captured. As the MERV rating increases, so does the filter's restriction level and the amount of pressure and energy needed to get air through.
This means that beyond a MERV 13 rating, a high-efficiency filter can cause more harm than good in a residential heating and cooling system. For this reason, MERV 13 air filters are ideal for homes with newborn babies and people with allergies, asthma, COPD, lung diseases or other health problems. MERV 13 filters can capture up to 90% of particles between 3 and 10 microns, up to 85% between 1 and 3 microns and up to 50% between them. Filters with ratings lower than MERV 8 are not effective at trapping many of the particles that pollute a home's air.
Therefore, MERV 8 filters are not usually suitable for people with allergies, asthma, and other health or respiratory problems. When choosing between a MERV 8 and a MERV 13 filter, you must consider what you want to filter from the air and why. A MERV 8 filter may be sufficient for some homes, while others would benefit from a MERV 13 filter. It is important to understand that as you increase your filter rating, you also increase your energy consumption due to increased pressure needed to get air through.
Therefore, it is important to find a balance between efficiency and indoor air quality. Understanding the MERV ratings, the differences between ratings, and the factors to consider when choosing a filter can ensure good indoor air quality for you and your family. Purchasing an air filter with a high-efficiency rating such as a MERV 13 will provide you with the cleanest air quality in your home.