How much does clean air cost?

Here in Fresno we have the worst air in the country — and you might expect clean air to cost a whole bunch, but it doesn't. When you go to the store, are you overwhelmed by the number of filter choices? Plenty of colors, sizes, prices, and ratings make things confusing and difficult. So which one will actually provide clean air for your home? The good news is that you don't have to buy the most expensive filter. It's important to note that if you're not changing your filters after at most 3 months of use, getting a filter that is too restrictive may cause premature failure of heating or cooling components.

Step 1: Choose the Right Filter Size

Next time you remove the old filter, check and make sure it fits tightly in the filter opening. If the filter is smaller than the return opening or filter slot, a majority of the air will flow around the filter instead of through it — which means you're getting almost no filtration benefit at all.

Step 2: Choose the Right Filter Depth

Once you've identified the correct length and width of the filter, the next thing you need to know is depth. Not all filters are 1 inch deep — you have the option of a 2 inch or 4 inch filter if your return opening or filter slot is large enough. The advantage of a deeper filter is that there is more filter material available to remove particulates from the air.

Understanding MERV Ratings

Filters are rated based on how small of a particulate they can filter out of the air. The standard rating in the industry is MERV (minimum efficiency reporting value), and you can find residential filters from MERV 1 up to MERV 12 and above. But as you increase the MERV rating, you also reduce the airflow through your system. This may not sound bad, but a majority of heating and air conditioning systems already operate with low airflow. Combining that with a restrictive high-MERV filter can cause serious problems — and in some cases permanently damage your system.

MERV Rating	What It Filters	Best For
MERV 1–4	Pollen, dust mites, carpet fibers	Basic protection, older systems
MERV 5–8	Mold spores, pet dander, dust mite debris	Most homes — good balance of filtration and airflow
MERV 9–12	Legionella, vehicle emissions, lead dust	Homes with allergy sufferers — check system compatibility first

There is also a rating system called FPR (Filter Performance Rating) that is similar to MERV and is primarily used by Home Depot to rate their filters.

Per year, clean air costs roughly $90–$120 depending on the size and MERV rating of the filter you choose.

But if it were only that simple — because of duct leakage and building leakage, you could install the highest-rated filter available and still be pulling in pollutants from leaky ducts or your attic and crawlspaces. Which is why it's important to have a whole house assessment performed on your home.

Contact Balanced Comfort for home energy audits and all your HVAC needs.