Choosing the Right Air Filter for Your Home


Choosing the right air filter for your home.

Colorado mountain air is fresh and invigorating, but if you ever find the inside of your home feeling stuffy, or your allergies flare up even when you’re not outside, it might be time to replace the air filter in your home.

While it is easy to forget and not change your filters until you start to see dust piling up on furniture and other surfaces, proper air filtration requires you to change the filters as part of a regular maintenance routine. Replacing a dirty air filter will not only help to reduce the allergens in your home, but also protect your air conditioning system from damage.

The standard recommendation is to replace your filter every 30-90 days, but during periods of heavy use, you’ll want to think about changing it closer to 30 days. This is especially true when your air conditioner is kept on all summer long.

The filters in your air conditioning system prevent dust and debris from passing through your ductwork where it can build up and decrease the efficiency of your A/C. Spending a few dollars on a new air filter now will help you save money in the long run, not to mention keep your house feeling fresh and pollutant free.  

When shopping for a new air filter, there are three main factors to consider: Size, MERV Rating, and the materials being used.


Determining the size of the air filter you need is the easy part. Most air filters will have their dimensions printed directly on them, so you can use that as a reference.

If you want to double check, the dimensions are usually shown as length by width by depth. Measure your air filter dimensions in that order and you’ll be good to go.  

MERV rating

Every air filter has a MERV rating, which stands for Minimum Efficiency Reporting Value. This rating is based on a scale of 1-20 and the higher the number, the better that air filter is at stopping contaminants and debris from passing through.

A filter with a MERV rating of 1-4 will stop about 60-80% of airborne particles. At the other end of the spectrum, a filter with a rating of 13-16 can stop 95-99% of airborne particles, and even smaller ones at that. Filters with a rating of 17-20 are slightly more effective, but are typically used  where absolute cleanliness is necessary – like hospitals and buildings with hazardous materials.

While you may be inclined to go with a filter that has a high MERV rating, you’ll want to consider the effect this has on your air conditioning system. A lower MERV rating may allow a slightly higher percentage of particulate to pass through, but this also means air can flow through your A/C a little easier. A higher MERV rating will cause your air conditioner to work harder as it needs to push air past the denser filters’ barrier.

When choosing an air filter for your home, you’ll want to consider the balance between air flow, efficiency, and the level of air filtration. We recommend a MERV rating of 6-8 for most homes. If you are prone to allergies, you may need to go slightly higher or even add a whole home air filtration system.  


When purchasing a new air filter, you’ll find that you can choose from a few different material types. Depending on the performance you are looking for, and the price you want to pay, these different materials give you plenty of options


Air filters with fiberglass cores are the most common and are typically more inexpensive than other types. They’re made with a fabric made of glass fibers that is dense enough to block most airborne particles. However, fiberglass air filters typically have lower MERV ratings as they can’t trap smaller particulate like pollen.

Polyester & Pleated Fibers

Pleated air filters are a great choice for the home as they have higher MERV ratings, usually 6 and up, and aren’t much more expensive than their fiberglass counter parts. These filters are made using polyester or cotton fabric that is pleated, providing more surface area to trap contaminants. These pleats also make it easier for air to pass through them, making a polyester air filter an efficient option.


Electrostatic filters are also made of a polyester blend, but have a positively charged outer layer and a negatively charged inner layer. As airborne particles pass through the filter and the first positively charged layer, they become charged and are attracted to the negatively charged material within the filter. This allows electrostatic filters to stop all sorts of particles, like mold and pollen. These filters typically have a MERV rating of 10 or higher.


For a reusable option, you can choose to install a washable air filter in your home. These filters are made of longer lasting, washable materials and feature an aluminum frame. The filter itself can last 3-5 years and should be washed every few months depending on air conditioning usage. When reinstalling these filters, make sure they are completely dry so they don’t grow mold.

If you have any questions on the type of air filter you should install in your home, give us a call at 720-307-4618. We can help you determine the best MERV rating and material for your application.

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