Best Air Purifier for Basement (Buying and Sizing Guide)

Best air purifiers for basement are GermGuardian AC5350B, SilverOnyx, Trusens and AIRMEGA

Looking to improve the air quality in your basement?

Want to get rid of mold, musty odors, or stale air that’s downstairs?

Then you’re in luck.

In this guide, we’ll show you how to find the best air purifier for basement spaces so the air in your house below ground-level stays clean and fresh.

The truth is that not all air purifiers are built the same.

And not all can handle the complexities of the air or size of a basement.

So, to help you get the right product for your needs, we’ll show you the top features to look for in the best basement air purifier models that make them perfect for underground spaces.

Best Air Purifier for Basement Comparison Chart

Here’s a chart showing the comparison between the top three basement air purifiers.

We’ll go more in depth about each one later in this guide but this gives you a sense of what’s available and an easy way to quickly compare them.

ImageNameFilter TypesCoveragePrice
GermGuardian AC5350BTrue HEPA, Carbon, UV Light167 sq. ft.$
SilverOnyxTrue HEPA, Carbon, UV Light, Ionizer500 sq. ft.$$
TrusensTrue HEPA, Carbon, UV Light750 sq. ft.$$$
AIRMEGA 300 and 400True HEPA, Carbon1,256 to 1,500 sq. ft.$$$

Why Use a Basement Air Purifier?

Before we jump into the features and reviews of the top basement air purifiers, we wanted to first go over why you should even use an air purifier in the basement.

The fact is that even though modern building practices are helping to reduce the problems associated with basement designs, there are still some issues that can’t be solved.

For example, some basements simply can’t have windows installed for ventilation because they’re completely underground. And others may have a walkout door but the soil grading on the sides of the home prevent windows from being added.

Additionally, not all basements have heating or air conditioning systems run to the lower level, which causes a lack of air movement.

As for the building materials inside basements, gypsum drywall is a known source toxic black mold to grow because it feeds off that material. And, carpeting absorbs moisture and other contaminants that are common in underground spaces.

Basements often have high humidity levels which cause a number of bacteria, mold, and fungi to grow, as well as odors to formulate. Dust is also very common in basement rooms because of the lack of air circulation.

What’s worse is that even if you don’t use your basement for living, the contaminated air and odors can still travel to the upstairs rooms.

For example, it’s quite common for the mold spores in a basement to float upstairs and cause a musty odor throughout the living area. It can also cause allergy symptoms to flare that you may confuse with dust mites.

As you can see, air purifiers are a much-needed device in basement spaces because these machines help to eliminate the particles and microorganisms that build up in below ground-level areas. And once those issues are taken care of, the rest of your home can benefit as well.

However, you need to ensure that you buy a top rated air purifier that contains a certain set of filters to keep your basement air fresh, clean, and free of pollutants, which we’ll cover next.

Top Basement Air Purifier Features

If you want to get the best basement air purifier possible, then there are a few must-have features you need to look for.

By getting an air purifier will the features listed below, you’ll eliminate the widest range of indoor contaminants in both finished and unfinished areas.

  • True HEPA Filter — This removes 99.97% of particles down to 0.3 microns in size (invisible to the naked eye). It captures dust, allergens, mold spores, smoke, and millions of other ultrafine contaminants.
  • Activated Carbon Filter — This removes particles that cause odors, musty smells, and stale air. It traps volatile organic compounds, chemical vapors, gaseous pollutants, and other pollutants that can’t be absorbed by a True HEPA filter.
  • Ultraviolet Light — This destroys microorganisms that live in basement spaces. As air passes through the air purifier, the ultraviolet light disrupts the DNA structure of microbes and pathogens, which renders them harmless to your health.

As you’ll discover below, each product in our list of the best air purifiers for basements includes these top features.

If you buy an air purifier that’s lacking any one of those components, it won’t work be as effective for cleaning your indoor air.

Getting the Right Size Air Purifier for a Basement

Now that you know what to look for in the top basement air purifiers, the next factor you need to consider is getting the right size unit.

Unfortunately, not all air purifiers have the same level of air cleaning power.

Each brand and model has a maximum range of room space that it can purify.

Therefore, it’s essential that you buy a device that can handle the full size of your basement (or the sectioned off area that you need to purify).

The truth is that if the air purifier is too small, then it won’t filter the air well enough and will also use more energy to operate. If it’s too large, then you’ll waste unnecessary money on the initial purchase and the unit will cycle on and off too much, which also increases energy use.

To get the right size air purifier, all you have to do is match up the machine’s square footage coverage with your basement space.

To get the right size air purifier, just follow these two simple steps:

  1. Measure the width and length of your basement. (Round the measurements up to make step two easier.)
    • If it’s unfinished, measure the entire space. If you’re only concerned with a partially finished area, just measure the space that’s enclosed by walls.
  2. Multiply the width by the length to get the total square footage (sq. ft.) for the area. For example:
    • A 25′ x 20′ unfinished basement = 500 sq. ft.
    • A 15′ x 13′ finished area = 195 sq. ft.

Once you have your total square footage number, you can proceed to look for an air purifier that can cover that amount of space. But, it doesn’t have to be a 100% exact match.

As long as the air purifier equal to or just above the size of your room, then you’ll be in good shape.

For example, if your basement room is 195 sq. ft., you could purchase an air purifier that covers 200 or 300 sq. ft., but a 500 sq. ft. unit would be much too powerful. And a 100 sq. ft. air purifier would bee too inefficient.

The Best Air Purifiers for Basements

Below are our recommendations for the best basement air purifiers for rooms of all sizes: small to large.

Read through each review to find the perfect device for your needs.

Basement Air Purifier For Small Rooms

Best air purifier for basement small rooms is GermGuardian AC5350BGermGuardian AC5350B

Covers up to 167 sq. ft.

If the room in your basement is small, like the one you find in a townhome or a sectioned off bedroom, then this may be all the air purifier you need.

Although it’s cheap, it still packs a lot of power.

This air purifier has all of the essential features to kills germs (Ultraviolet Light), trap allergens and dust (True HEPA filter), and reduce odors (Activated Carbon filter).

It also has a slim design and doesn’t take up much space, which is crucial in small areas.

This product comes in two colors: black and white, and you also have the option of upgrading to the Wi-Fi enabled version so you can control every aspect of it from your mobile device.

See Amazon Reviews

Basement Air Purifier Medium to Large Rooms

Best basement air purifier for medium to large rooms is SilveryOnyxSilveryOnyx

Covers up to 500 sq. ft.

If you need an air purifier for an average size basement, this is going to be your top choice.

In addition to the essential features every high-quality basement air purifier must have, a True HEPA filter, Ultraviolet Light, and Activated Carbon filter, this model also includes an Ionizer to boost its air cleaning power.

The ionizer emits charged ions into the air to neutralize contaminants as they float around. This feature also helps to extend the life of the internal filters so you don’t have to replace them as often.

The best part, however, is the actual design of this machine. It includes 360-degrees of air filtration, as opposed to one-sided like many other air purifiers.

The cylindrical shape increases the surface area of the internal filters by 60% which makes it much more efficient too.

See Amazon Reviews

Basement Air Purifier for Large Areas

Trusens air purifier for large areasTrueSens

Covers up to 750 sq. ft.

If you liked the idea of our last review, but need to cover a bit more space, then this air purifier should meet your needs.

It too has 360-degrees of air filtration but goes one step further by including dual outward airflow that splits clean air into two streams. And in some cases, this unique design has been proven to be up to 24% more efficient.

Another top feature that this product includes that others don’t is a SensorPod. This SensorPod is placed on the other side of the room to monitor to help monitor the total air quality inside the basement. If pollutants are detected far away from the machine, it will report back to the air purifier so the device can automatically adjust itself to take action.

With every other air purifier brand, particles much hit the sensor located on the unit before adjustments are made. So, the SensorPod helps the Trusens air purifier react faster to indoor contaminants.

Finally, while we’re recommending this as the best air purifier for large basement areas, it does also come in smaller sizes. The medium size model covers up to 375 sq. ft. and the smaller model covers up to 250 sq. ft.

So, you definitely have options when it comes to this brand.

See Amazon Reviews

Basement Air Purifier for Very Large Areas

AIRMEGA 300 and 400 air purifiersAIRMEGA 300 and 400

300 Series Covers up to 1,256
400 Series Covers up to 1,500 sq. ft.

If you have a very large finished or unfinished basement and need an air purifier to keep it clean and fresh, then your best choice is to go with this AIREMEGA brand here.

However, it’s important for you to understand that you won’t find an air purifier that can cover more than 750 sq. ft., like the previously reviewed Trusens model, which includes an Ultraviolet light.

If you want total coverage in a very large space for killing airborne pathogens and microorganisms, it’s best to buy two Trusens air purifiers are run them together.

The other option is to just invest in the AIRMEGA 300 or 400 model air purifiers.

With these machines, you get an Advanced Max2 Filter that combines a True HEPA filter for capturing ultrafine allegens, dust, and bacteria, with an Activated Carbon filter to get rid of Volatile Organic Compounds and odors.

Although the AIRMEGA air purifier can’t destroy mold spores or fungi, it still does an excellent job of purifying the air from every other contaminant.

Finally, both models also come in a Wi-Fi enabled version called the 300S and the 400S. So, you can choose to control it with any mobile device if you desire to have that feature.

See Amazon Reviews

Additional Information on Basement Air Purifiers

Benefits of Using an Air Purifier in the Basement

At the beginning of this guide, we went over a few basic reasons for why it’s a good idea to use an air purifier in the basement.

However, there are many more benefits than just getting rid of mold spores, musty odors, and dust.

Air purifiers offer so much more for your health and comfort.

What you’ll find below is a list of the top benefits you’ll enjoy by running an air purifier in your basement, whether it’s finished or unfinished.

  • Better Air Circulation — If you don’t have or can’t open windows in the basement, an air purifier can help circulate the air for you. Room air is drawn into the unit, filtered, and then pushed back out into the space. This cycle creates flowing air which helps keep the air from getting stale and making the area more comfortable to be in.
  • Less Dust — As air is circulated through the air purifier, dust particles become trapped in the True HEPA filter. This reduces the amount of dust from collecting inside your basement.
  • Fewer Allergens — There are hundreds of different types of allergens that invade basement areas. Like dust, these allergen particles get trapped inside the True HEPA filter.
  • Lower Level of VOCs — If you have a finished basement or store any sort of chemicals in the lower level of your home, chances are you have VOCs (volatile organic compounds) seeping into the air. VOCs leak out of building materials, paints, varnishes, carpeting, drywall, and more. An air purifier with an Activated Carbon filter can eliminate these gaseous pollutants before they accumulate to unsafe levels in your basement or float to the upstairs.
  • Reduction in Mold Spores — Practically every basement is prone to getting mold. The lack of ventilation, control of temperature, and humidity all play a factor in mold growth. An air purifier can slow down or stop the spread of mold spores in your home by capturing those particles in the True HEPA filter. And the Activated Carbon filter can reduce mold odors.
  • Fresher Air — With all of the above contaminants remove from your basement air, it will become much fresher and cleaner. This makes it more suitable to use your finished basement as a living space and store your valuables and belongings in an unfinished area with less worry about them getting damaged.

Best Ways to Use an Air Purifier in the Basement

Unfortunately, air purifiers don’t always come with the best instructions for basement applications.

Since people use air purifiers in so many different rooms of the home, it can be hard for a manufacturer to address every need.

So, to help you get the most benefit out of your basement air purifier, we put together this list of tips for you to follow:

  • Center it in the Room — If you can put the air purifier in the exact center of the room, you should do it. Otherwise, centering it on the wall with about 24 inches of clearance behind the unit is your next best option. This location will allow the air purifier to draw the most amount of air through the filters without creating dead air spots.
  • Place it on the Floor — Putting the air purifier on the ground level is better than having it higher up on a table. Heavier contaminants fall out of the air and are more easily sucked into the machine at a lower height. Also, common floor level particles, like dust, can be pulled into the air purifier at an easier rate.
  • Always Keep it On — Many air purifiers come with automatic shutoff timers, and Wi-Fi versions have scheduling capabilities. However, the best way to use an air purifier in the basement is to keep it running 24/7. The second you turn off the air purifier, pollutants can start to accumulate inside the room. In a basement, you want the air to constantly be cycled through the filters so it stays fresh and clean 100% of the time.
  • Keep Up with Filter Changes — Depending on the size of the air purifier you buy, you’re looking at changing the internal filters every 6 to 12 months. While you may be tempted to push your filter changes past these limits to save some money, it’s not a good idea because your air purifier is only as good as the filters inside. As the filters collect pollutants, they get clogged and dirty, and at a certain point, they become inefficient. You don’t want that to happen in a basement since you’ll then be circulating dirty air.

More Ways to Improve the Air Quality in Your Basement

Using an air purifier in your basement is just the first step in improving your air quality.

While an air purifier can definitely clean the indoor air of harmful particles and odors, it can’t make up for poor maintenance issues that may be affecting the basement.

In addition to having an air purifier downstairs, you should also do the following:

  • Seal up Cracks, Gaps, and Holes — Polluted air, allergens, dust, bacteria, and mold can seep into your basement small cracks, gaps, and holes. So, go around your downstairs level and seal up any noticeable areas around windows and entry points with caulk or foam filler.
  • Keep Windows Closed — When you’re running an air purifier, you want all windows shut. This allows the unit to fully recycle the indoor air through the filters over and over again until it’s clean. If the windows are open, outdoor contaminants and moisture can flow inward and defeat the purpose of running the air purifier at all.
  • Add a Dehumidifier — Basements are prone to moisture issues and high humidity levels, which promote the growth of mold and bacteria. Adding a dehumidifier to this space to keep humidity levels around 50% RH can prevent those microbes from growing.
  • Inspect (and Repair) Any Insulation — Having good insulation will help in regulating basement temperatures which also improves overall air quality.
  • Deep clean the Floors, Walls, and Ceiling — Take a day and do a thorough cleaning of every surface in your basement. Be sure to wear a respirator and protecting clothing and gloves. Doing a deep clean like this can eliminate a large number of contaminants that may be reproducing in your basement space.
  • Only Use Low or Zero VOC Paints and Stains — If you’re remodeling your basement, make sure to only use paints and stains that don’t contain VOCs. The price may be more expensive but it will be much better for your health. Paints and stains with VOCs can take years to fully off-gas out of the material since it occurs at such a slow rate.

We hope this guide on finding the best air purifier for basement spaces helped answer all of your questions and concerns on purchasing this type of device.

Regardless of the best basement air purifier model you choose on this page, you’ll enjoy a fresher, cleaner basement for years to come.