Home Air Filters: Simplified

by Lysi Bishop Real Estate

Home air filters are arguably one of the most important components of any home cleaning system, yet they are often the least understood.

It’s easy to become lost in the complex acronyms and detailed charts on what air filters homeowners should and shouldn’t use. As homeowners ourselves, and with over 25 years of experience in the real estate industry, we know a thing or two about the important and not so important parts about air filters.

Personal health takes priority.

Whatever the reason for looking for a proper air filter, always consider the members of your household. Consider allergies, special illnesses, asthma, sensitivities, etc.

Air filters will filter the air inside the home, but remember, all air originally comes in from outside. Depending on where you live, consider the air quality outside the home and how it can affect your health. This is especially true for areas that deal with seasonal smoke during fire season.

Here’s a link to a great resource for checking the air quality in your area.

Seriously, change those air filters.

Yes, you really do need to change your air filter at least every 3 to 4 months. In fact, some researchers suggest every 2 to 3.

Here’s a few reasons why:

When air filters are clean and free of debris they can help lower your energy bills. When air filters are regularly replaced, your HVAC (Heating, Ventilation, and Air Conditioning) system will overwork itself less often, will need less maintenance, and avoid expensive repairs.

Air becomes easily stagnant or trapped in a house even while fans create airflow, unless those particles are getting filtered, they stay in the home.

General dirt, dust, pollen, smoke, or pets reduce the air quality. This is especially true during winter to spring, and summer to fall when pets shed the most.

What does MPR, MERV, FPR mean? Does it matter?

It’s easy to get stuck on the numbers, so we’ll keep it simple for you:

The higher the number, the more it filters, the more strain it puts on your HVAC, the more it’ll raise your energy bill.

Our advice? Unless someone in your household struggles with air quality for health reasons, most homes will be fine using a low to medium quality filter as long as you remember to replace it regularly.

But really, what do all of these acronyms mean?

Each of these are air quality rating systems, here’s a quick review:

MPR (Microparticle Performance Rating): (300 - 1900) This system rates the manufacturer's filter and is the most familiar in hardware stores. It only grades a filter based on it’s capacity to remove particles.

MERV (Minimum Efficiency Reporting Value): (MERV 6 - MERV 13) This is the international industry standard and primary rating system. This grades a filter based on its ability to capture and hold particles. The higher the rating, the more particles are trapped.

FPR (Filter Performance Rating): (1 - 10) Created and used by Home Depot, this one is very similar to MERV in how it grades a filter. The higher the number, the more effective it is.

Again, we recommend using the lower to mid-grade filters, most homes will be just fine using those as long as they are replaced regularly.

(Sensing a theme?)

Choosing an air filter and alternatives.

Choosing an air filter is important, but shouldn’t be complicated. After considering your comfort level and needs, remember that even the lowest grade filter is still a good choice, and to replace it regularly.

If you’re looking for alternatives, here’s a quick Q&A on the most commonly researched options:

Q: Do reusable air filters work?

A: Although they tend to be more expensive, reusable filters have a longer lifespan, save money in the long run, and are more environmentally friendly. However, according to industry professionals, they do have their drawbacks, such as lower filter scores, and can attract mold and mildew if not cleaned and dried properly.

Q: Are UV lights in HVAC systems effective?

A: Yes. Studies show that UV lights are a very effective (and expensive) way to prevent microorganisms in air ducts. Like HEPA (High Efficiency Particulate Air) filters, UV lights are commonly only used in hospitals and laboratories and are generally not recommended public use. Consult with a professional before installing.

Q: Would an Air Purifier be a good substitute?

A: No. Although air purifiers do help move and clean air in the home, it is not a suitable replacement for the filter that runs through a home’s duct system.

Q: Do DIY box fans with air filters work?

A: Yes and no. According to researchers, they work to a degree. Neither the filter nor the fan were built for that intended purpose, but they are effective in situations such as quickly clearing smoke or dust out of an enclosed area.

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