unifinished basement with exposed wall studs

If you have a basement, you’ll undoubtedly experience some sort of air quality issue down there.

The most common problems include high levels of dust, dampness, and musty odors.

If you’ve ever noticed that unpleasant basement smell or felt like that area of your home can never stay clean, you’re not alone.

In this guide, we’ll show you the top tips for how to improve basement air quality.

By the end, you’ll have everything you need to create a clean, dry, and fresh smelling basement that’s inviting for people to use.

How to Improve Basement Air Quality

1. Clean the Air

The most simple way for how to improve basement air quality is by cleaning the air.

To do that, you need to invest in an air purifier.

Air purifiers are devices that circulate the air through a set of filters and strip out the contaminants that are floating around.

This includes microscopic particles such as dust, allergens, mold spores, bacteria, and more.

The only catch here is that you need an air purifier that contains certain features in order for it to create the cleanest air possible.

Those features include a True HEPA filter, Activated Carbon filter, and Ultraviolet light.

That combination of features can reduce up to 99.97% of harmful airborne particles down to 0.3 microns in size as well as remove musty odors and kill off germs.

You can find out more about those features on the best air purifiers for basements here.

You’ll also learn how to get the proper size air purifier for your basement so you don’t buy a unit that’s too big or too small for the space.

Several of the products listed in that buying guide are also included in our best home air purifier page which lists the overall best 10 products available today.

See all of Amazon's Best Selling Air Purifiers

2. Dry it Out

Many problems with basement air quality stem from dampness and humidity.

So, if you can dry out your basement, you can eliminate a lot of the issues that produce musty odors and cause that “icky” feeling you may have when downstairs.

When a basement has increased moisture in the air, it promotes mold and mildew growth.

In an unfinished basement, you can often see the visible signs of mold on the ceiling, joists, walls, or floor.

In a finished basement, you may not see the physical signs of mold but only smell it because the mold is hidden behind drywall, carpeting, or ceiling covers.

Mold is not just smelly but also causes a wide range of health problems in people, like coughing, sneezing, nasal congestion, eye irritation, and allergic reactions.

In order to prevent mold from forming, and to stop it from growing, you need to dry out your basement.

Mold needs moisture to survive and without it, mold will die.

The simplest thing you can do is add a dehumidifier to your basement.

A dehumidifier will work to lower the relative humidity that’s in the air.

The ideal range you want to aim for is 30-50%. Anything under 50% will prevent mold from surviving.

3. Ventilate

Ultimately, the major reason why basements have such bad air quality is the fact that they’re poorly ventilated.

Air gets trapped inside the basement and doesn’t get recycled with cleaner outside air.

To help improve the ventilation—and air quality—in your basement, you can install a mechanical ventilation system to bring fresh outside air indoors.

These systems don’t require windows and most are energy efficient.

The only downside is that these systems can be expensive and require professional installation by a qualified HVAC technician.

If you can afford it, it’s a good investment; however, you can often get the same results by using an air purifier and dehumidifier in the same room for much less.

4. Keep Windows Closed

If you have windows in your basement, you may think that opening them is the best way to improve the air quality downstairs.

Unfortunately, this is not always the case.

Especially during the summer months when humidity rises and outdoor allergens are more prevalent.

Opening the basement windows can cause the indoor humidity to rise (which promotes mold growth) and draw in allergen particles (which pollute the indoor air).

So, the best advice here is to keep the windows closed, if you do have them.

5. Seal Up Cracks and Gaps

Similar to opening a window, any cracks or gaps around the basement foundation walls, windows, or doors can lead to higher humidity levels and contaminated air flowing in.

To keep your basement air quality protected, it’s best to seal up all cracks and gaps in those areas with caulk or expanding foam.

6. Remove High VOC Contributors

Many of us use our basements to store chemicals and solvents like paints, stains, lacquers, and gasoline.

And since most basements have poor ventilation, the fumes from these chemicals, called “volatile organic compounds” or “VOCs” can build up to toxic levels and make the air quality worse.

If you can remove these high VOC contributors from your basement, that’s the best course of action.

Putting these containers in the garage or an outdoor shed is a better location.

It’s also a good idea to throw away any chemicals or solvents you’re not going to use anytime soon so you can further reduce your potential exposure to dangerous fumes.

If you’re curious as to what the level of VOCs are in your basement, consider getting one of these best home air quality monitors. An air quality monitor can measure the level of VOCs in the air so you can know if they’re a problem or not.

7. Use Low-VOC Paint

Did you know that many paints contain volatile organic compounds (VOCs) and these chemical vapors can off-gas for months, if not years?

That means, if you paint your basement with a paint that contains VOCs, you could be exposed to toxic gases for an indefinite amount of time.

To stay safe, only buy paints that have low or zero VOCs. That way you can limit your exposure to these toxic chemicals.

8. Test for Radon

Sadly, more than 21,000 people die each year from lung cancer that’s brought on by being exposed to radon inside their homes.

Radon is an odorless gas that forms from the natural breakdown of uranium in soil, rock, and water and gets into your home through basement floors, foundations, joints in the walls, and other openings.

Having a professional radon test is the best way to find out of your home does have a radon problem.

If dangerous levels of radon are found in your home, you don’t have to move.

Instead, you can have a mitigation system installed that pumps the radon out of your home and into the outdoor air.

Every Basement’s Air Quality Can Be Improved

Now that you know how to improve basement air quality, you don’t have to suffer from it being bad anymore.

By following the tips outlined above, you can have a clean, dry, and fresh smelling basement for years to come.

As we mentioned in the first tip, a cheap and effective way to clean the air downstairs is by adding an air purifier to your basement.

You can find out how to choose the perfect device for your needs on the best air purifiers for basements here.

And, if you want to see what the overall best air purifiers are for all areas of your home, take a look at our top air purifiers page.

We hope the information in this guide was helpful for you to improve the air quality in your basement.

Avatar for Katherine Dyson

About Katherine Dyson

Katherine is the lead Staff Writer. She conducts in-depth research and interviews with industry experts in order to produce a wide range of content for the site. Her main role is to write helpful articles that aid people who are seeking to improve their indoor air quality and comfort. (See Full Bio)