(Last Updated On: June 27, 2023)

How Many Air Purifiers Do I Need?

In theory, you would get the best results by having an air purifier in every room of your home. However, the cost of doing this can make it impossible for most people. If you can afford two air purifiers, choose one for your bedroom and one for the living area. But if you can only afford one, you’ll want to put it in the room where you and your family will receive the most benefit.

Air purifier in a modern living room.

First, Start By Measuring Your Room

Once you choose where your air purifier is going, you’ll want to know the square footage of the space. Every air purifier is designed to cover a certain amount of square footage, so it’s important to make sure the air purifier you choose covers the space you plan to put it in. Instead of guessing at your room size, grab a measuring tape and measure the length and width of the room. Multiply those two numbers to get the area. For example, if your room is 10 feet by 15 feet, the square footage is 150.

  • Room Size: 10 x 15 = 150

But just because the air purifier’s box says it covers rooms up to 150 square feet doesn’t mean it’s the right size for your room. That’s because the square footage coverage number on the air purifier box is usually based on ceilings that are eight feet tall. Your home may have ceilings that are taller than eight feet. If that’s the case, then you will have to calculate the cubic footage of the room. So, let’s say your 10 x 15 room has 10-foot ceilings. Here’s how to find the cubic footage:

  • Room Size: 10 x 15 = 150 square feet
  • Cubic Footage: 150 (square footage of room) x 10 (ceiling height) = 1500

So, with the cubic footage above, you’ll need an air purifier that covers at least 1500 square feet. You’ll also want to pay attention to how many times the air purifier cleans that amount of square footage an hour – the more the better. If the box says the machine will cover up to 150 square feet, that generally means it will clean that amount of space on the highest fan speed once an hour.

How to Optimize Air Purifier Usage

Air purifiers can be expensive, and they perform an essential function, so you want to make sure it serves you well. It’s important to take good care of the machine and there are some simple steps you can take to keep it performing like it’s supposed to.

Filter Replacement
All air purifiers work with a filter and all filters have a lifespan. Some last longer than others, but the general time frame is usually between 6 and 15 months. One of the most important things you can do to extend the life of your air purifier, and ensure you’re breathing clean air, is to replace the filter when it’s recommended.

Whether it’s time to change the filter or not, you should check it at least once a month. Depending on the quality of the air or how hard the purifier has had to work, the filter may get dirtier quicker, and may need changing before the recommended time. If the machine you have contains a permanent filter, make sure you clean it regularly. That will extend the life of the air purifier and the disposable filter.

Clean the Air Purifier
Just like everything else, air purifiers need to be cleaned. Dust the outside of the machine as often as you dust inside your home to make sure there’s no unnecessary build-up. And at least once a month, wipe down the area inside the purifier where the filter goes. It will help keep your machine running longer.

HVAC Filters
Just like the filters for your air purifier, the filters for your HVAC need to be changed regularly. These filters help protect the sensitive components of your HVAC system, while also filtering out large particles like dirt, dust and hair.

HVAC filters should be changed, on average, every three months. If you have pets in your home, you should change the filter every two months. If you have more than one pet or suffer from allergies or respiratory problems, you should change the filter once a month.

Air Purifier Placement
You may not realize that where you put your air purifier is just as important as how often you run it. Where the machine sits can affect how well it performs. If the air purifier is in your bedroom, place it near your “breathing zone.” Typically, placing it on a night stand or near the head of the bed will be most effective.

If the air purifier is in the living room, it’s best to place it off the ground and near places with the highest air flow—think doorways, near windows, and along walls. Don’t ever put your air purifier directly behind a curtain or piece of furniture. That will obstruct the machine and keep it from performing correctly.

Air Quality Monitoring
More and more air purifiers are coming equipped with air quality monitors. These machines will track air quality in real-time and adjust the fan speed accordingly. But if your air purifier doesn’t have one, it may be worth investing in an air quality monitor. That way you can know when to turn the fan speed of the purifier up to clean the air.

When to Replace Your Home Air Filters

As mentioned, it’s important to replace the filters in your air purifier regularly to keep the machine working correctly and to make sure the air inside your home is as clean as it can be. But there are several factors that can result in the need to replace the filters more often than the recommendation on the box.

For instance, if you or someone you live with has pollen allergies, you will want to change the filters more often during pollen season. This is especially true if you like to open the windows on warm, spring days.

If there is a smoker in the house, you’ll want to change your filters more often. Tobacco smoke has been proven to be a health hazard. Because of the way it sticks to other particles in the air, it has the tendency to linger much longer. For those reasons, it can dirty up filters quicker than other pollutants and create the need for them to be changed more often.

Some air purifiers contain activated carbon filters. They’re highly effective at removing odors, gasses and VOCs from the air by adsorbing them into the porous material. Because of the process, these filters have to be changed out about every three months.

What Factors Affect Filtered Air Quality?

If you’ve done any research on air purifiers, you’ve likely heard of ionization. Some machines are equipped with ionizers which use negative ions to remove small particles from the air. Ionizers will help mask the smell of odors in your home and make the air seem fresher.

The problem with ionizers is they can also emit ozone, which is an unhealthy lung irritant. Inhaling small amounts of ozone can cause an immediate reaction including chest pain, coughing, difficulty breathing, shortness of breath, and throat irritation. Over time, breathing in ozone can make asthma worse, give you a higher risk of respiratory infections, reduce your lung function, and cause lung inflammation. It’s a good rule of thumb to stay away from air purifiers with ionizers, or turn the ionizer off if the machine has that option.

Are Air Purifiers Good for the Environment?

When in use, air purifiers are a great addition to your home to help clean the air inside. We don’t truly realize all the irritants that can be floating around in our homes on any given day. Whether it’s dust, allergens or gasses and VOCs, an air purifier can pull those things out of the air, trap them in the filter and send fresher, purer, more breathable air back out. Eliminating those things are good for the environment because if left alone, they can lead to chronic health issues.

The units run on electricity, but most companies make them energy efficient so you’ll see very little difference in your electric bill. The air purifiers and filters themselves aren’t recyclable. They may eventually end up in a landfill, which can be an environmental mark against them. But air purifiers are generally made to last and don’t have to be frequently tossed out and replaced, which makes the environmental benefits outweigh the risks.

Our Top Rated Air Purifiers

Alen Breathesmart 45i $429 Buy Now
Austin Air
Healthmate Plus
Air Purifier

$855 Buy Now
Air Purifier

$900 Buy Now
Classic 605
Air Purifier

$495 Buy Now
AirMega 400
Air Purifier

$450 Buy Now