1. Air Filters Buying Guide
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How to buy an air filter

An air filter buying guide

If you are wondering how to buy an air filter that will work well to keep your home's ventilation clean, you will need to consider a few different factors, including the filter's size, type and rating.

>> Consider the environment

how to buy air filter

An air filter is an essential component needed for your living space to help keep you healthy. Before you decide to shop for air filters for your home and look at air filter advantages, it is necessary for you to consider the environment that the air filters will be needed for. Different types of air filters target different pollutants. It is important for you to determine which pollutants possibly exist within the air you breathe at home. Airborne particles are the most common and include pollen, fungi, tobacco smoke and pet dander. If you have anyone living in your home that suffers from allergies, be sure to look at air filter designs that target those allergens.

If you are living in an environment that is commonly subject to odor from a litter box, cooking fumes, aerosols or pesticides, an air filter that cleans the air with a carbon filter works best. Volatile Organic Compounds (VOCS) are also an ordinary occurrence in many homes that must be filtered out accordingly. VOCS come from many common household cleaning items, such as disinfectants, paints, chloride or glue. Not removing VOCS from the air may cause certain health symptoms like a sore throat, headache or eye irritation.

>> Consider size

best air filters

While learning how to choose an air filter, you must consider air filter sizes before making your choice. These sizes vary depending on your heating, ventilation and air conditioning (HVAC) system. If you are unsure of the specific size needed, consult your HVAC system's owner's manual for proper specification. The normal size specification that is found on most packaging is the approximate size that is rounded to the nearest inch. This is done to make it much easier to perform an air filter comparison. The actual size specification is the exact measurement.

As you learn how to buy an air filter and become more familiar with home improvement tools and materials, keep in mind that the air filter should fit tightly within your HVAC system for proper heating, cooling and air quality. This is why thickness also plays a role when determining the best air filters for your home. Air filter sizes are able to be as small as one inch thick or as big as four inches or more. The best air filters for your HVAC system need to fit tightly. A filter that is too loose may let additional pathogens flow around it and into your home.

>> Consider types of filters

types of air filter

When considering different types of air filters to choose from, the types of air filter material chosen has a large impact on what is filtered out of the air. The standard filter that is often used in most homes is known as the HEPA (High Efficiency Particulate Air) filter. HEPA filters are required to remove at least 99.7% of particles as tiny as 0.3 microns. HEPA filters are able to trap mold spores, animal dander and pollen, while needing to be changed every 2 to 3 months. Although these filters feature standard guidelines put in place by the U.S. Government, they feature many different styles and types of material.

Consider using this air filter comparison chart to help you figure out how to buy an air filter for your living space.

Type of Air Filter


Electrostatic - Ability to capture variety of particle sizes,from small to large
Washable - Ability to be cleaned and used again- Replacement is needed once every few years- Protects older style furnace motors
Pleated - Recyclable- Allows for larger air flow- Ability to remove particles as tiny as 1 micron
Polyester or Fiberglass - Best at capturing large particles like dust- Economically priced- Recyclable

>> Consider air filter ratings

air filters comparison

As you shop for air filters, you will notice that most types of air filter packaging feature what is known as a Minimum Efficiency Reporting Value (MERV). When considering how to choose an air filter size for your space, this number tells you how well this filter is able to trap particles, which range in size from 3 microns to 10 microns. The higher the MERV number is the better that the filter is able to trap a larger amount of particle sizes. Most air filters feature a MERV number between 1 and 12.

On certain types of air filter packaging, you will also see the MPR (Microparticle Performance Rating). This rating system depends on the brand of different types of air filters. As with the MERV number, the higher MPR means a higher number of air filter advantages. MPR often shows the filtration rating for certain types of particles, such as bacteria or smoke.

>> Consider additional features

how to choose air filter

After learning how to buy an air filter by looking for the proper specifications for your home, you are able to consider additional features to keep the air quality high. Certain air filter designs are able to be used in conjunction with a standard air filter in order to purify the air. An activated carbon filter works to filter out certain odors and gases that are able to pass through a standard filter. By using the process of adsorption, activated carbon has millions of tiny open pores that feature surface areas large enough to neutralize harmful particles.

A pre-filter is made up of nylon or foam and has the ability to filter out large particles in order to pre-clean the air before filtration from a standard filter. This process utilizes electrostatic to help cut down on odors while removing airborne pathogens like pet hair. A pre-filter has a lifespan of 2 months before it needs to be changed. An electrostatic air filter uses static electricity in order to clean the air. When the air in your home flows through a number of fibers, an electrostatic charge is created. Airborne particles are attracted to this charge and attach to the filter. This type of air filter needs to be washed every 1 to 3 months and has the ability to be reused again.

Determining which air filter to buy for your home depends on the allergens and odors you are looking to get rid of. Be sure to read up on your HVAC system's specifications to determine the size that you are able to choose from. By knowing how to buy an air filter, you can improve the air quality of your home in an effort to help keep your family healthy.

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