Choosing the Right MERV Filter for Your Needs MERV Rating: As mentioned earlier, aim for a MERV rating of 11 or higher for optimal asthma control.
Whole House Air Filters for Asthma
Instead of getting the cheapest air filter for your furnace or HVAC system, look for a disposable filter with a minimum efficiency reporting value (MERV) of 11-13. The higher the MERV rating, the better.
Consider HEPA Filters
For the most effective allergy and asthma control, consider High-Efficiency Particulate Air (HEPA) filters. HEPA filters are known for their ability to capture 99.97% of particles as small as 0.3 microns.
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.
Because not all HVAC systems can use HEPA filters, air filters with a MERV rating of 13 to 16 are the best option to trap pollen, pet dander, mold spores, and dust mites, and they're highly effective for reducing allergens and improving indoor air quality.
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.
Filters with a MERV rating of 8-13 are usually higher-end filters for home use or high-quality commercial filters. These filters are typically the right choice for use in homes and many businesses.
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.
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.
The higher-rated filter also captures up to 50 percent or greater of the smallest particles floating through the air. The primary benefit when comparing a MERV 11 vs. MERV 13 filter is that the latter includes stronger protection against airborne bacteria and viruses that spread through droplets in the air.
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.
Eventually, congested filters become secondary sources of indoor pollution. Dust accumulations support vast microbial colonies, especially in humid climates. Mold, bacteria and dust mites that live in dirty filters may trigger allergies and asthma.
Air purifiers with a High Efficiency Particulate Air (HEPA) filter, a recognised international standard, should be the preferred choice for filtering airborne viruses, bacteria, allergens, and other particles such as dust and smoke. H13 filter grades or higher remove ≥99.9% of particles sized larger than 0.3 microns.
For most homes, the best HVAC filters for summer are cotton or polyester pleated filters of MERV 8 to 10. A MERV 8 filter traps almost 85% of particles down to 3.0 microns.
The highest VA disability rating for asthma is 100%. This rating is reserved for veterans with severe asthma symptoms that significantly impact their daily life and ability to work.
When the AQI is 101 or higher, it is unhealthy for people with asthma. You may have to change your activities and medicines. If you have asthma, your symptoms can worsen even when AQI levels are moderate (AQI 51-100). Many local weather forecasts warn the public about high air pollution days.
For most allergy sufferers, a MERV rating of 9-12 is ideal.
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.
The abbreviation stands for Minimum Effective Reporting Value. In other words, it's a measurement showing how small the holes are in the filter. The higher the MERV number, the smaller the holes, and the less that can pass through. Ultimately, this is what makes MERV 14 filters not a good choice for home use.
MERV‑8 filters are among the most popular choices because they strike a balance between performance and adaptability, fitting most systems without modifications. However, it's worth noting that filters with higher MERV ratings can restrict airflow.
MERV 5-8 filters need to be changed roughly every 3 months. MERV 9-11 filters require replacement every 6 months. MERV 12-16 filters should be replaced about every 9 months.
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.
Choosing the Right Furnace Air Filter for Winter
For most residential furnaces, filters with MERV ratings between 8 and 13 offer a good balance of filtration and airflow.
The 3M Filtrete Ultra Allergen Filter stands out due to its ability to capture microscopic particles like dust, smoke, and smog while also removing allergens such as mold spores and pollen.
MERV 11 is still highly effective for homes, filtering common allergens and larger particles. Choosing between them depends on your system's capacity and air quality needs—MERV 13 if air quality is a priority, MERV 11 for balanced filtration and airflow.