This may not seem like a significant difference compared to the merv 8 filter, but a Merv 11 is also better able to capture between 65% and 79% of the smallest particles. Based on the characteristics mentioned above, a MERV 8 is considered superior filtration compared to air filters with a lower MERV rating. But is that enough leakage? In many cases, a MERV 8 air filter is more than adequate. However, if you are concerned about outdoor air pollution, family members with respiratory problems, pets are in the house, then choosing a higher merv rating might be a good idea.
MERV 11 filters are more efficient than MERV 8 filters because they can capture smaller particles. They offer additional protection against pet dander, dust mites, automatic emissions and dust that damages the lungs. This is a good choice for homes with pets or those looking for even better air quality than what the MERV 8 can offer. It is also our most popular type of air filter.
The air filter in your home's heating and cooling system is used to clean the air before it is distributed throughout the house. If you are new to air filter selection, you may not yet be sure which option is best despite the detailed explanation above. A higher MERV rating often means lower airflow, which can cause the system to work harder and use more energy to do its job. Although merv 13 is suggested by the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE), it may not be the most efficient option for some residential HVAC systems.
MERV 13 are the denser filter types discussed here, so they need to be changed more regularly than types with lower MERV ratings. The MERV scale is not linear; the difference between a MERV 6 and a MERV 8 is almost double in the percentage of particles captured. If someone has an allergy or respiratory problem, use a Merv 11 air filter or even a Merv 13 air filter. Since MERV 11 filters have denser fibers than MERV 8 filters, they tend to fill with trapped debris more quickly.
One consequence of a very effective air filter is the speed with which it can be loaded with contaminants and begin to increase the pressure drop. When the air filter is dirty, less air can pass through the HVAC system, increasing operating times and reducing efficiency. Keep in mind that as the MERV rating increases, the filter becomes more restrictive and more pressure and energy will be needed to push air through it. What you probably already know is that the MERV rating is a measure of how effectively the filter removes materials from the air flowing through it.
The type of MERV rating isn't the only thing you need to consider when servicing your HVAC system. When removing the old filter, be sure to pay attention to the direction in which the arrows point to the filter to know which direction the air filter enters. If your home's HVAC system isn't capable of handling MERV 13, opt for a filter with the next highest possible rating. These types of filters are enough to trap particles as small as 1 micron, such as car exhaust fumes, pollen and mold spores.