Best Air Filter for Your Home In general, the best MERV rating for a home is somewhere between 8-10. These filters will capture a large portion of the airborne particles and improve indoor air quality without making your energy costs rise significantly.
For most homes, a MERV rating between 8 and 13 strikes the perfect balance between filtration, airflow, and cost. A MERV 11 filter, for instance, can last up to six months and offers excellent air cleaning without putting too much strain on your HVAC system.
In most cases, a MERV 11 air filter isn't too high for residential use. Generally speaking, anything under a MERV 13 air filter should provide very efficient air purification in a home without impacting airflow.
HVAC professionals say MERV 8 is the highest you should go. Filters are there to protect the equipment not you. The higher the MERV rating the harder the furnace has to work. 1/2x a year change the filter unless you have pets then change 3/4x a year.
A MERV 13 filter is capable of filtering out all particle impurities like dust, lint, pollen, mold, dust mites, pet dander, smog, and smoke. On top of this, it can also trap bacteria and viruses. MERV 11 furnace filters have a particle arrestance of a little over 90%.
Any air filter with a rating higher than 13 will restrict air flow to the point of which could cause damage to your HVAC system, resulting in an added expense to fix it.
The MERV 11 air filter is the wrong choice for people who do not own pets and do not have any breathing trouble; this is because it can lead to restricted airflow. Air filters with higher ratings can also have negative effects on HVAC components.
High-MERV filters increase the static pressure of your system, and if the ductwork is already marginal, this can cause the airflow to drop to a level where the temperature exceeds the furnace's limit.
HEPA Filters
With a MERV rating nearing 16, HEPA filters provide the highest protection for your home. They're able to remove even the smallest microns or airborne particles, including tobacco and bacteria. Those who live with allergies or other respiratory issues may benefit from HEPA filters the most.
A MERV rating between 9-12 or even higher would be good if someone in your family suffers from allergies or asthma. A MERV 11 filter can trap particles such as dust, dust mites, pollen, pet dander, mold spores, lint, and larger particles.
MERV 13 Air Filters
Filters with higher ratings are intended for healthcare and laboratory environments with excellent air quality and HVAC systems that can handle highly efficient filters. Using a filter above MERV 13 in a home is unnecessary and can restrict airflow and damage the HVAC system.
Generally, this is how long a filter lasts based on MERV ratings: MERV 1-4 furnace filters should be replaced once a month. MERV 5-8 filters need to be changed roughly every 3 months. MERV 9-11 filters require replacement every 6 months.
MERV Rating
A rating between 1 and 4 will protect your HVAC system, but will not improve air quality. A rating between 5 and 13 is useful in fighting mold, pet dander, bacteria, and some viruses. Anything rated at a 14 or higher has the highest efficiency.
ASHRAE currently recommends using a minimum MERV 13 filter, which is at least 85% efficient at capturing particles in 1 µm to 3 µm size range. A MERV 14 filter is at least 90% efficient at capturing those same particles.
One disadvantage of the highest MERV rated filters is that: The pressure drop across high MERV filters is more.
Well, MERV ratings range from 1 to 20, with 1 being the lowest level of filtration, and 20 being the highest. Filters that are MERV 16 through 20 are usually only found in hospitals, cleanrooms, and nuclear power plants. The home air filters you're looking for have a MERV rating anywhere between MERV 5 and 13.
Pleated filters with MERV ratings from 5 to 8 are classified as medium filters and are the most common in residential HVAC systems.
One of the main disadvantages of air purifiers with HEPA filters is the need to replace these filters regularly to maintain their effectiveness. A HEPA filter should be changed every 6 to 12 months, depending on its use and the environment in which it is used.
Pleated air filters can restrict airflow to some extent due to their denser construction and larger surface area. Non-pleated air filters generally have lower airflow resistance compared to pleated filters.
1“ Throw Away Filter
1” throw away filters are typically a MERV 2 rating. Most Bard products can use either a 1” throw away or a 2” throw away filter. Upgrading from a 1” filter to a 2” filter will give you a higher filtration value. Remember to reference your manual for what your Bard product is capable of handling.
Filters within a MERV rating of 17-20 are almost never necessary in a residential home. A MERV rating of 13-16 is considered hospital level air quality, so it is unlikely your home needs any more than that.
MERV 13 filters typically need to be changed every three to six months. However, the frequency with which you need to change your filter depends on a number of factors, including: The type / brand of filter you're using. The size of your HVAC system.
Sometimes, a MERV 11 filter may be too restrictive, particularly for older or smaller HVAC systems not designed to handle the increased pressure drop. If you notice that airflow has diminished or your HVAC unit is cycling on and off more frequently, these could be signs that your filter is too restrictive.
Generally, most air filter manufacturers and HVAC companies recommend changing your air filter every 90 days, or 3 months. That can change based on where your home is located (ex. dusty, dry climates), if you have any pets, and the age of your system and equipment.