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Understanding Home Air Quality Levels
Air quality in the home, in your business and in schools is more important than you may realize. Learn all about indoor air quality in this guide, including common pollutants and tips to remove them.
What Is Home Air Quality?
Humans spend roughly 90 percent of their time indoors, where the concentrations of certain air pollutants can be anywhere from two to five times higher than outdoors, as noted by the Environmental Protection Agency (EPA). This underscores the importance of indoor air quality, which includes air quality in the home, office, school and businesses. Air quality in the home refers to the amount of air pollutants present. These pollutants can cause a range of health concerns including short-term symptoms like itching and sneezing to long-term health problems, according to the EPA.
Signs of Poor Air Quality in the Home
There’s no single sign to alert you. However, the EPA suggests that health effects can occur after being exposed to indoor air pollutants just once or they can happen after repeated exposure. Commons symptoms include the following:
- Eye, throat and nose irritation
Whether you have a reaction depends on how sensitive you are to the different pollutants. The symptoms can also seem similar to coming down with a cold or virus. If you experience symptoms that go away after you leave home, the air quality in the home might be the root of the problem.
How to Monitor Indoor Air Quality
If you’re concerned about the air quality in your home, a monitor could be a good solution to help you keep your eye on things. The following monitors are recommended by Electronic House:
- Wave from Airthings tests for radon, humidity and temperature. It connects to an app on your phone to deliver notifications and reports.
- Speck from Airviz Inc. tests for small air particles and connects with an app on your mobile device to deliver reports and data.
- Awair from Bitfinder tests for large air particles, VOCs, humidity and carbon dioxide. It also provides solutions for you to improve your air quality.
Biggest Offenders That Wreck Indoor Air Quality
Some of the biggest culprits behind poor indoor air quality include small air particles like dust and dander, and large particles such as pollen. Other concerns include:
- The volatile organic compounds (VOCs) found in some chemicals, cleaners and paint
- Carbon monoxide, which may be released by fuel-burning home appliances
- Carbon dioxide, which is often released by home heating systems
Tips for Improving Air Quality in the Home
Improving your indoor air quality can potentially reduce allergy symptoms and asthma flareups, according to Harvard Health Publishing. To improve the air quality in your home, follow a few tips:
- Regularly vacuum carpets and area rugs with a HEPA filter-equipped vacuum at least once a week.
- Regularly wash bedding, drapery and other items that could attract dust mites and allergens.
- Change the filters in your heating, ventilation and air conditioning system regularly according to manufacturer recommendations.
- Consider using an air purifier to capture some of the irritants you can’t control.
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How to Improve Basement Air Quality
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.
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.
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 )
How to Improve Air Quality in Basement
Having a basement in the home is so nice. Whether it is a finished or unfinished basement, it adds more space to the home, storage, and entertaining. However, sometimes the basement can have poor air quality. Are you wondering how to improve air quality in the basement? There are several ways. Use an air purifier, dry the moisture out, keep windows closed, seal cracks and gaps, remove VOC’s, test for radon , and monitor carbon monoxide.
Let’s take a look at why it is important to improve air quality, how to improve air quality, maintenance to keep air quality clean, and when to contact a professional.
Why It is Important to Improve Air Quality in Basement
Good air quality is important. We need to make sure that we are breathing clean air each day and not air that is full of allergens and chemicals. Sometimes it is hard to know though but there are steps we can take to ensure it is as clean as possible.
Here is a great video to help understand why it is important to have good air quality in the basement.
Improving air quality in the basement can be done and in very simple ways. Let’s take a look at those ways.
Air Purifier Will Improve Air Quality in Basement
An air purifier is a great way to improve air quality in the basement as it circulates the air through a set of filters. Then, it takes out the contaminants that are floating around in the room. The air purifier needs to include a True HEPA filter, Activated Carbon Filter, and Ultraviolet light in order to get the cleanest air possible.
You will want to find one that is the proper size for the room you are using it in. One that is too small won’t work well so having the correct size is important. Many of the air purifiers are labeled with the size in square feet of the room they are good to use it in. Thus, knowing the size of the room is important before ordering or buying one. In addition to this improving the air quality, it also helps for ventilation issues.
Cost: About $100-$300 or more depending on size of the room.
Get the Moisture Out
Getting the moisture out of the basement is important. Moisture often causes the smell and dampness you find in a basement with poor air quality. When we have moisture, there is an increase in mildew and mold in the basement. You will need to clean the mold and mildew with protective gear after you find the source.
Do you know where the moisture is coming from? This is important to find out. Sometimes it can be from a leak in a window when it rains or can be the floor drain is backing up in the basement . The moisture can be coming from numerous places such as behind the drywall, ceiling covers, or carpeting. Don’t fret, a home inspector can use thermal image devices to find the water leak .
In an unfinished basement, look up at the ceiling as you may see mold on the joists or trusses. This can happen in the building process when the wood is left out in the rain and moisture. Sadly, it is often left at job sites on the ground.
The fungi are attracted to wood because of the cellulose in it and this allows the fungi to feed and spread. Then, the mold will grow if the temperature is between 50-90 degrees and has 30% moisture in the wood. Unfortunately, rot can also happen and structural issues. You will want to contact a professional to help take care of the issue.
Symptoms from the Mold
Some of the yucky air you are breathing in can be harmful, especially if it is mold. The mold can cause symptoms such as nasal congestion, allergic reaction, sneezing, coughing, and eye irritation. Add a dehumidifier to the basement to get the humidity at 30-50% and this will help.
Keep Windows Closed to Improve Air Quality in Basement
This might sound like a great way to ventilate the basement or to get fresh air in. In the cooler fall months and spring, this would be okay if the pollen and allergens are low. However, if it is summer or the pollens and allergens are high, then this is not a good idea. What it will do is bring in the polluted air and also higher humidity and you don’t want that.
Seal Cracks and Gaps
Check the basement for any cracks or gaps and seal those right away. You don’t want air escaping the house or air coming into the home. This will contribute also to the high humidity and moisture and this is what you are trying to avoid.
Remove VOC Chemicals to Improve Air Quality in Basement
Often when we paint the home, we will keep the leftover paint in the basement. However, this is not a good idea as the fumes are powerful and pollute the air. Keeping the paint and other volatile organic compounds (VOC’s) such as solvents out of the home and in the garage will clean up the air. Buying an air quality monitor is a good idea so you can keep an eye on the air quality if you are concerned.
Cost: $30-$200
Thinking about painting your basement? Choose a zero or low VOC paint such as this one . If not, you may be exposing your family to toxic gases.
Testing for Radon
Radon enters a home through the cracks in the foundation, building joints, well water, or exposed soil such as a basement or crawl space. It can be found in homes with or without a basement. Some people think that opening the windows will get the radon out, but unfortunately, it does not.
Here is a great map that shows what the radon levels are in the U.S. Every home should be tested no matter where it is as all radon has to do is enter the home where the building attaches to the soil.
Monitor Carbon Monoxide
You will want to monitor the carbon monoxide if you have a furnace. One way to do this is by looking at the furnace. If you see a yellow or flickering flame, moisture around the windows or walls, or rust on the vent pipe you may have a carbon monoxide issue.
If you do, get the family out of the home right away and call your HVAC company and gas company. Another way to monitor it is to get a carbon monoxide detector. Carbon monoxide is a poison that will seriously harm or cause death.
Maintenance To Keep the Air Quality Clean
Change the air filter in HVAC – changing this out every 90 days can help keep the air clean. If your home has smokers or pets, you may need to change it more often. This is part of a great plan for spring HVAC maintenance.
Keep firewood outside – don’t store firewood in the basement. Keep it outside away from the home. Firewood creates moisture and will add to the moisture in the home and grow mold or mildew.
Install exhaust fan – If you decide to finish the basement, install an exhaust fan to pull out the moisture.
When to Call a Professional
Call a professional if you are not sure what is causing a musty or dirty smell in your basement. Also, if you are thinking about finishing your basement and need a quote, a professional is a good one to contact. Lastly, there can be a lot of hidden dangers in homes with an unfinished basement or furnace so keep an eye on maintenance and signs of trouble. Reach out to a professional if you need assistance.
A basement is great to have but it does need to be clean and have good air quality. Keep an eye on any signs that there may be a problem and look into fixing the issue. Having an air quality monitor is a great idea as well as doing your part to keep mold and mildew out of the home. Boggs Inspection Services can complete indoor air quality testing on your home.
Dwayne Boggs
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5 Basement Air Quality Problems & Solutions to Finally Enjoy Your Basement
It is not uncommon for basement space to go unused because of high levels of dust, dampness, and musty odours that create an unpleasant environment. However, you can make the most of your living space by improving your basement’s air quality. Here we cover five basement air quality problems with solutions to help you finally enjoy your basement.
1. How to Make Basement Air Fresh to Get Rid of Musty Smells
Poor indoor air quality can lead to unpleasant musty smells created by things like excess dust, moisture and pollutants in the air. The best way to make your basement air fresher is to use air filtration to help purify the air. There are two types of air filtration products:
- Electronic Air Filters: This filter removes airborne pollutants and contaminants such as cigarette smoke, pollen, bacteria, virus, mould and dust from your home.
- Mechanical Air Filter: This filter removes dust and other irritating particles attracted by your HVAC systems blower fan. They are ideal to circulate clean air by removing particles and sending clean air back into your basement.
Your HVAC specialist can recommend the best filtration solution for your needs.
2. How To Get Rid Of Dampness In a Basement Apartment
Basements are prone to dampness issues because they are surrounded by concrete and built underground with little ventilation offered by windows. Signs of dampness in a basement might include mould growth, damp walls, condensation, a musty smell, or a moist feeling on books and other papers. A dehumidifier can help reduce dampness in the basement to improve poor air quality.
3. How to Take a Basement Air Test to Find the Cause for Poor Quality Air in Basement
If you feel your basement just doesn’t feel right or is constantly producing a smell whether it is musty, mouldy, dusty or mildewy, you can purchase a basement air testing monitor. Advanced models can detect:
- Harmful odourless gasses
- Volatile organic compounds (VOCs)
- Airborne particulate matter (PM)
- Humidity levels
- Temperature
This can help you identify air quality issues, so you know a) if it is dangerous and b) the causes. If you detect mould or gasses, you can call in the professionals to help rid you of the issue. However, if it has to do with VOCs, PM, humidity or temperature, your local home comfort expert can offer solutions. They can install an air purifier, dehumidifiers, or recommend filtration products. If your HVAC system is faulty they might also recommend replacement.
4. How to Improve Basement Ventilation Due to Poor Air Circulation
Basements are notorious for poor air circulation. This tends to be one of the major causes of that unpleasant smell and feel in your basement. Because air isn’t circulated, bad air gets trapped and is never recycled with clean outside air. A lack of windows just makes matters worse. A mechanical ventilation system helps bring fresh air into your space. However, you can also opt for an air purifier which helps provide the same results at a far lower cost.
5. How to Use Fresh Air Systems in the Basement to Reduce Air Pollution
Using an air purifier helps keep the air in your basement smelling fresh while also preventing you from breathing in pollutants. The best models use ultraviolet light to get rid of odours helping rid your basement of that musty smell.
Are you concerned about the quality of air in your basement and looking for solutions? Contact the experts at Woodbridge GTA ClimateCare today to get help.
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How To Seriously Improve Your Indoor Air Quality
Let’s play Truth or Dare, shall we? Yeah, baby. Are you psyched? Are you scared? I’ll go first. Truth, I say! (You can tell what kind of kid I was—in other words, not the kind to streak across the neighbor’s lawn.) Have I ever dry cleaned an item of clothing and/or cleaned with conventional cleaners? Gulp. Well, one time I… I mean, it was just a… I didn’t think it was. Silence. Can I skip this round?
Your turn. Dare, you say? (Whatever. It doesn’t make you inherently cooler.) I dare you to get a vacuum with a HEPA filter and stop using air fresheners! Wait, what? You already do that because you know it seriously improves your indoor air quality? I want a do-over.
For more content like this follow
The Environmental Protection Agency states that the air quality within homes can be more polluted than the outdoor air even in the largest and most industrialized cities. But there are things you can do to seriously improve your indoor air quality and make your home a healthier place .
Find out how… if you dare.
Know the Pollutants
According to the Environmental Protection Agency , there are 3 categories of indoor pollutants, all of which have the potential to cause serious health problems with enough exposure:
1. Combustion Pollutants : gases or particles that come from burning materials, including space heaters, woodstoves, gas stoves, water heaters, dryers, and fireplaces that are either improperly vented or not vented at all. Types and amounts of pollutants produced will vary depending on how well the appliance was installed, maintained, and vented, as well as what kind of fuel it uses. A few common combustion pollutants include carbon monoxide and nitrogen dioxide , both of which are colorless, odorless gases.
2. Volatile Organic Compounds (“VOCs”) : a variety of organic chemicals that are released as gases from certain solids or liquids. They’re widely found in household products, including paints and varnishes, cleaning and disinfecting supplies, building materials and furnishings (such as composite wood products), pesticides, craft materials like glues, adhesives, and permanent markers, air fresheners and other synthetic fragrances, dry-cleaned clothing and textiles, carpets, sealing caulks and solvents, vinyl, personal care products and cosmetics. A few common VOCs are: Acetone, Benzene, Ethylene glycol, Formaldehyde, Methylene chloride, and Perchloroethylene. For more help, learn how to read labels and avoid toxic cleaning products.
3. Asthma and Allergy Triggers : common household triggers include mold, dust mites, pollen, secondhand smoke, and pet dander. At any given time a home may have mold growing on a shower curtain, dust mites in soft textiles like pillows, blankets or stuffed animals, and cat and dog hair on the floor and upholstery.
Maxwell vacuuming the filter from his air purifier.
Take Steps To Reduce Your Exposure
Once you’ve identified the culprits polluting your indoor air, reduce your exposure with a few simple habits:
- Open the windows as much as possible, even just for a few minutes.
- Clean or change all the filters in your house regularly, particularly those for your heater or furnace, air conditioner, air purifier, and vacuum. Follow the manufacturer’s instructions and stay up to date.
- Adjust your humidity levels accordingly with a moisture or humidity gauge, available at most hardware stores. Ideal in-home humidity levels should hover around 45%. Anything under 30% is too dry, over 50% is too high and can contribute to mold growth. To increase humidity, use a vaporizer or humidifier. To decrease humidity, open the windows (if it’s not humid outside), turn on a fan or air conditioner, or use a dehumidifier.
- Stay away from synthetic air fresheners and petroleum-based wax candles. Opt instead for homemade air fresheners , simmer pots , and all-natural soy or beeswax candles which won’t emit any harmful chemicals.
- Use a HEPA air purifier. Make sure to get an air purifier that does not produce ozone, and one that does eliminate VOCs that off-gas from paint, furniture, and cleaning chemicals. Check out this guide on how to shop for an air purifier that best suits your needs.
- Get some green plants, particularly one or more of the plants on this list from NASA . Just one of these plants for every 50 feet in your home could help reduce VOCs and improve air quality.
- Groom your pets regularly.
- Paint with low or no VOC paint . Always choose non-toxic adhesive, finishes, and varnishes where possible. (A reputable manufacturer should be upfront about the ingredients.) Be informed about the different materials that go into a piece of furniture, and what is likely to offgas.
Unplggd managing editor Gregory tests out the Electrolux Ergorapido 2-in-1 Sweeper , which he says is “the best hard floor vacuum for pet owners.”
Clean Smart.
- Use eco-friendly, non-toxic cleaners and supplies or make your own cleaners.
- Invest in a very good vacuum with strong suction, rotating brushes, and a HEPA filter, which traps smaller particles and allergens that regular vacuums miss.
- Minimize carpets or choose low-pile rugs. Vacuum at least once a week, including walls, carpet edges, and upholstered furniture. Wash or change your vacuum filter regularly.
- Buy a reusable microfiber dust mop, which are good reaching into the nooks and crannies that the vacuum can’t reach. Wipe down tops of doors, window frames and sills weekly with a damp cloth. Wash curtains often.
- Use good quality dust-mite-proof pillow, mattress, and box spring covers in the bedroom, organic if possible. Avoid carpet in the bedroom completely. Wash sheets and blankets once a week. Keep clothing off the floor and shoes out of the room.
- Green clean the mold in your shower and regrout if necessary.
For other essential reading on indoor air quality, check out these resources from the Environmental Protection Agency:
- Indoor Air Quality Home Page
- Care For Your Air: A Guide to Indoor Air Quality
- Guide to Air Cleaners in Your Home [PDF]
- Healthy Indoor Environment Protocols for Home Energy Upgrades [PDF]
- Indoor AirPLUS Label for New Homes
(Images: 1. Morguefile ; 2. Maxwell Gillingham-Ryan; 3. Gregory Han;)
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Improving Air Quality in Your Home’s Basement
Home / Articles that Educate / Improving Air Quality in Your Home’s Basement
March 25, 2019
Posted in: HVAC-Tips
Tagged: Basements , heating and cooling , indoor air quality , mold
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If your home has a basement, you may be familiar with that unpleasant “basement smell.” Residential basements provide some special challenges in terms of indoor air quality. A basement itself have high levels of indoor pollutants. Those pollutants can get into the rest of your home through the floors and doorways.
So if you want to improve your home’s indoor air quality as a whole, it’s important to address the air quality in your basement. Let’s take a look at some of the pollutants most commonly found in basements and methods to reduce or eliminate them.
Dry It Out to Avoid Mildew and Organic Growth
The most common basement problem is dampness and humidity . Water often seeps into basements through the concrete walls and floor. Sometimes it’s just enough water to make things damp; sometimes it’s a flood!
Either way, water in the basement leads directly to the number one cause of that “basement smell”: organic growth and mildew. Finished basements can be particularly prone to these culprits. This is because carpets and wallboard can absorb and hold the moisture that seeps in through the concrete.
The organic growth and mildew can begin growing on the underside of the carpet or the back of the wallboard. In all of the areas where you can’t see it. By the time a small visible spot appears on the surface, you may have a massive organic growth problem underneath.
Organic growth doesn’t just smell bad. It also releases spores that can cause a wide range of health problems when inhaled. Organic growth is a serious indoor air quality issue. It can lead to symptoms like nasal congestion, sore throat, coughing, wheezing, eye irritation, and allergic reactions. In people with asthma, organic growth can trigger or worsen asthma symptoms.
See Also: How Flooring Affect Efficiency and Air Quality
What To Do To Prevent Organic Growth and Mildew
So to prevent organic growth and mildew in the basement, you need to keep it dry. According to the U.S. Consumer Product Safety Commission, basements shouldn’t be finished unless they are completely waterproofed. They also need to have adequate ventilation and heat to avoid condensation.
If you install carpet directly on the concrete floor in the basement, the CPSC advises that you must install an moisture barrier underneath the carpet. Otherwise it will draw up moisture from the ground via capillary action.
Additionally, the CPSC recommends using a dehumidifier . This is to keep the basement’s humidity level between 30-50%. If the basement is conditioned space, a whole-home dehumidifier can be used to keep the basement’s humidity in the ideal range along with the rest of the house.
If you store items in your unfinished basement, watch out for signs of dampness and water damage. Keep in mind that organic growth grows very well on cardboard boxes.
Test for Radon
Another serious basement air quality hazard is radon . According to the CDC, this radioactive, odorless gas causes approximately 20,000 deaths from lung cancer in the United States each year.
A 2018 article published in the journal Environmental Science and Pollution Research International explains that because radon is a heavy gas that seeps up from deep underground, basements are particularly prone to high radon levels.
The U.S. Department of Health and Human Services recommends that when you have radon testing done, you perform the test on the lowest level of your home that is used as living space.
So if you use the basement for living space—not just for storage—then you want to make sure you test the radon levels in the basement, because they could be significantly higher than the levels in the rest of the house.
If dangerously high levels of radon are found in your home, then you’ll need to have mitigation performed by a qualified contractor in order to protect yourself and your family from this deadly gas.
Watch Out for Chemical Fumes
According to the ESPRI journal article, another common source of basement air pollution is items stored in the basement. Many homeowners store chemicals such as paints, lacquer, solvents, and gasoline in their basement. This can also include storage of gas-powered equipment.
Fumes from these chemicals can pollute the basement’s air and ultimately rise up through the floors or doorways into the rest of your home. Without outside ventilation, these fumes can become highly concentrated in the basement, making the air quality even worse.
Take care when storing chemicals in your basement. Don’t just stick them in a corner and forget about them! Make sure they’re properly stored in sealed containers and clean out your “stash” regularly to reduce the potential exposure to dangerous fumes.
Ventilation is Key
Ultimately, the biggest reason that basements suffer from poor air quality is a lack of ventilation . Because basements rarely get enough fresh, outside air, the indoor air pollutants build up into higher concentrations.
If you’re using the basement as living space, it’s particularly important to ensure adequate ventilation. A mechanical ventilation system, such as an ERV, can bring in fresh outside air without sacrificing energy efficiency.
That will help to improve the air quality in your basement, which in turn will improve the air quality throughout the rest of your home. And that’ll help you and your whole family to breathe a little easier!
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6 Ways to Improve Basement Ventilation
Imagine what you can do with your basement once that lingering musty odor is gone
If your basement feels stuffy or musty, it's likely because of poor ventilation. But there are ways you can resolve this problem, from reducing humidity to installing new vents. The following tips can help you improve your basement space and its air quality, so that activities like hosting game day watch parties and endless ping pong tournaments can resume.
Why Should You Ventilate Your Basement?
Mildew and musty odors are just a few culprits that can pop up in unventilated basements. With small windows in the basement, ventilation doesn't just happen on its own. Rain, running the clothes dryer, or moisture coming through the concrete can cause the basement air to become more humid. If left unchecked, poor air circulation can potentially lead to radon gas accumulation or cause carbon monoxide to build-up.
But don’t panic. With a few easy steps, you can turn your beautifully finished basement into a place that’s pleasant to spend time in again.
1. Utilize Natural Ventilation
If your basement is humid and filled with stale air, natural ventilation is one solution for creating fresh airflow. This method reduces moisture and saves energy. Just open up your windows and doors to let in some fresh air.
If you don’t have any windows in your basement, consider installing new windows —the more windows you install, the better the airflow. The process may be a bit of an investment, but windows are a necessary ventilation component. They will also help when installing additional ventilation tools, such as exhaust fans. Install new egress windows in a location where they are protected from extreme weather conditions.
2. Install Vents
Vents help your space breathe—they exchange stale air with fresh air and allow circulation between rooms.
If leaving your basement door or window open all the time is not an option, a vent by the basement door will aid in more airflow. An energy recovery ventilator (ERV) whole-house ventilation system works well for areas of the home that benefit from outdoor air, like a basement. The system preheats or precools incoming air while also managing water vapor. The result is better air quality with less humidity.
3. Invest in an Air Purifier
Air purifiers suck in stagnant air and pass it through a series of filters. These filters catch dust particles, mold spores, and allergens, before pushing out clean air into your basement.
4. Dehumidify
The EPA suggests that homeowners should maintain humidity under 60% to control the growth of mold and mildew in their basements.
If your basement air is humid, you may want to invest in a dehumidifier. A dehumidifier effectively reduces moisture accumulation to ensure a more livable and comfortable environment that isn’t a haven for mold. Just be sure to pick a dehumidifier that fits the size of your basement, which can cost between $800 to $2,000 .
5. Use Fans
A high-performance exhaust fan in the basement bathroom will get rid of moisture. An exhaust fan works by pushing stale air out of your basement and forcing fresh air to come in.
You must vent your basement into an open outdoor space (a crawl space or an attic won't be effective for this project type). Fans can be installed in a vent pipe, windows, or might require cutting through a basement wall.
If you can’t install an exhaust fan, you can use a box fan to improve ventilation. They're small, portable, and only cost around $50 to $250 .
6. Extend the HVAC System to the Basement
Extending the HVAC system to the basement could be a good idea to consider if you're remodeling your basement . A central AC system draws in air from inside the home, passing it through a filter and cooling it until the air reaches the desired temperature.
This system benefits basement ventilation by creating more airflow, making it ideal throughout the year. In addition, forced air systems contain dehumidifiers, which means that the air pumped into your home is relatively free from any moisture. The cost of installing a central air conditioning system in your home ranges between $5,000 to $12,500.
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Air Quality
Basement air purifiers that improve air quality, explained.
Introduction
Basements are a great feature of a home, and quite practical. A finished basement typically is considered space one could live in – it has insulation, drywall and is centrally heated. Its rooms can be used for any purpose like home offices, playrooms, home theaters, in-law suites, laundry rooms, among others. An unfinished basement, on the other hand, doesn’t have these features, so it’s prone to dust, dirt, and is often rarely used by homeowners.
Table of Contents
What’s Inside the Air in Your Basement
Volatile organic compounds (vocs).
VOCs can cause respiratory discomfort, asthma, and allergic reactions. Some have even been named Group 1 carcinogens, meaning that they will cause cancer at certain levels of exposure.
Microbial Volatile Organic Compounds (mVOCs)
Carbon monoxide.
Carbon monoxide is a colorless and odorless gas that can become lethal quickly. Because it’s hard to detect, it’s known as the silent killer. Carbon monoxide forms under two conditions in your home. There is either a lack of oxygen in the air, so carbon monoxide forms instead of carbon dioxide. Or, faulty appliances that give off heat don’t vent properly and allow carbon monoxide to build up inside the home instead of outside.
Particulate Matter
Particulate matter is a general term that’s used to describe broadly the particles that are suspended in the air. As you can imagine, particulate matter can contain many things, like gases, dust mites, dirt, smoke, atmospheric air pollutants, etc.
How to Improve the Air in Your Basement
Control the moisture in the air, get a good dehumidifier, divert water away from your house, don’t give mold a chance, stop the food source for mold.
If your house is still being built or you’re about to finish an unfinished basement, avoid organic building materials in the basement that mold can feed off of.
Clean and Remove Any Existing Mold
If you have a more serious mold issue, remember that disinfectants and filters have their limitations. Disinfectants work for only 48 hours, so you may have to clean the area a few times before you notice that the mold is gone. Filters only trap mold, so the mold could still be in your home giving off toxins.
How do you know if you’ve properly cleaned up the space? Once you see no visible mold, come back a few days later and keep checking the space for a certain period of time. If the mold doesn’t come back, then you’ve probably cleaned up the space from the mold. If the mold does come back, you must clean it up again. Remember to keep the area dry and keep the relative humidity (RH) low to keep the mold from recurring.
Test for Radon
The EPA recommends testing your home for radon every year, but unfortunately, most homeowners don’t heed this advice. If you have a basement, radon should be especially important. Radon tends to be found in the soil where there is radioactive rock in the soil. Areas where coal, volcanic rock and limestone exist, for example, can contain radon. When in the ground, it’s referred to as uranium, which then decays into radon once it’s inside the home. However, don’t let the geography fool you. Poorly constructed homes can make a home vulnerable, no matter what the uranium level in the soil is!
( The detector used in the video is the Corentium portable radon detector and is made by Airthings. )
Prevent Carbon Monoxide
High levels of carbon monoxide can be lethal. For that reason, most homes have a carbon monoxide detector. Imagine the alarm going off in the middle of the night, while you’re sleeping on the upper floor of the house. If the level is high enough, you may only have minutes before the carbon monoxide level becomes lethal.
Declutter and Throw Away Old Items
If you treat your basement like a shed or storage unit, then it needs a thorough cleaning if you want to improve the air quality of your overall home.
If your basement still has unpleasant odors after a thorough cleaning, consider introducing bamboo charcoal air-purifying bags . They’re a natural way to trap odor-causing particles. Just keep in mind that bamboo charcoal needs to be set outside once a month to clear out the pores in the charcoal. If you absolutely want a light fragrance to freshen the space, choose a natural neutralizer instead of a harsh air freshener that just masks the odors.
Filter the Fine Particles Out
A lot of that is out of our control because of outdoor air pollution, but some of it is possible to control. For example, laser printers are notorious for releasing fine particles. If you have a basement home office, keep the printer under an opened window, or upstairs and print wirelessly. If you have a kitchen in the basement, either turn on the exhaust fan when cooking or cook upstairs in the main kitchen.
Monitor and Maintain Your Indoor Air Quality
Hopefully, the information above has served as a checklist to you. Once you have taken care of some of the more alarming issues, all you need to do is to monitor and maintain the air in your home.
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Staying Healthy
Easy ways you can improve indoor air quality
Reduce indoor allergens that can trigger respiratory problems and other issues..
It may feel cozy being sealed in tight against the cold in your home during the chillier months of the year, but for people who are sensitive to indoor allergens or have respiratory problems, winter can exacerbate problems. Stale indoor air and heating systems can increase the amount of allergy-inducing dust mites, pet dander, and mold spores circulating through your house. In late winter and early spring, it may still be too chilly to throw open the windows to pull out the musty air, so while you await the warmer weather it's important to be aware of some of the allergy and respiratory triggers that may be lurking in your surroundings.
"Most of the things that cause problems are odorless," says Dr. Nicholas BuSaba, associate professor of otolaryngology at Harvard Medical School. "So, in many cases there's nothing to alert you to the problem." That is, there's nothing other than the symptoms these allergens can trigger — such as respiratory problems (including asthma flare-ups), fatigue and sleepiness, or even digestive issues.
Indoor air quality tends to be worse in the winter months because there is often no flow of fresh air from the outside, meaning allergens stay trapped inside.
Improving air quality
Making an effort to improve indoor air quality can help you avoid asthma flare-ups and allergy symptoms and keep you breathing easy through the colder months.
While it's probably not possible to eliminate all the allergens inside your home, you can reduce the number — and your exposure to them — by making some simple changes. Here are some strategies you can use to improve air quality inside your home and hopefully improve your allergy symptoms.
Keep it clean. A clean house may be a healthier house, because good indoor hygiene can greatly cut down on dust and animal dander, says Dr. BuSaba. Your cleaning efforts should focus on strategies to reduce the accumulation of pet dander, mold, and dust lurking in your home. Focus on the following:
Vacuuming the carpets and area rugs at least once or twice a week with a vacuum cleaner equipped with a HEPA filter. Opting for hard-surface flooring instead of wall-to-wall carpeting may also cut down on allergens in the home.
Regularly cleaning bedding, drapes, and other items that tend to attract allergens—particularly if you have pets. The American Academy of Allergy, Asthma & Immunology recommends washing in water that is at least 130° F. Also consider using dust mite–proof covers on pillows, as well as mattresses and box springs, whenever possible.
Clearing clutter, because it traps and holds dust that can trigger a reaction.
Keep the greenery outdoors. Indoor plants are pretty, but they can also collect and foster the growth of mold. So, if indoor allergens are a problem, you'll want to avoid them, says Dr. BuSaba.
While some plants are touted as helping to improve indoor air quality because they release oxygen, they are still allergy triggers for many people. "On balance, they create more problems than they help," he says.
Change your filters. If you have a forced-air heating system, be certain to change the filters regularly, says Dr. BuSaba. Electrostatic filters can help ensure that dust and other airborne irritants get trapped instead of being recirculated throughout your home.
Also consider having your ducts cleaned to remove trapped dust. This may not always be advisable, but it helps in some cases. The Environmental Protection Agency offers advice on making this decision at /iaq.
Invest in an air purifier. If you're allergic to indoor allergens and can't control the source of the problem — for example, you're unwilling to give up your family pet — it may help to use an air purifier, says Dr. BuSaba. Placed in the most commonly used areas of the house, these devices, in particular ionic purifiers, can help capture some of the irritants that may trigger your symptoms. You're probably not going to be able to remove these allergens completely, but you can cut down on them, which may help the problem.
Also consider a dehumidifier in damp areas, such as a basement, to help prevent the growth of mold. Ensure that bathrooms, another potential source of mold, are well ventilated as well and scrub off any visible mold that collects in the shower, on fixtures, or walls.
Let the fresh air in. Even in the cold months, open windows from time to time to allow fresh air to move into the house. Also, move potential air contaminants out by using fans in the kitchen to remove cooking fumes.
Disclaimer:
As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles.
No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.
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How to Improve Basement Air Quality · 1. Clean the Air · 2. Dry it Out · 3. Ventilate · 4. Keep Windows Closed · 5. Seal Up Cracks and Gaps · 6. Remove High VOC
Air Purifier Will Improve Air Quality in Basement · Get the Moisture Out · Keep Windows Closed to Improve Air Quality in Basement · Seal Cracks and
Using an air purifier helps keep the air in your basement smelling fresh while also
1. Keep Basement Windows Closed. It may seem counterintuitive to keep your windows closed to ensure better air quality. · 2. Ventilate Your
Clean Smart. · Use eco-friendly, non-toxic cleaners and supplies or make your own cleaners. · Invest in a very good vacuum with strong suction
Ultimately, the biggest reason that basements suffer from poor air quality is a lack of ventilation. Because basements rarely get enough fresh
1. Utilize Natural Ventilation · 2. Install Vents · 3. Invest in an Air Purifier · 4. Dehumidify · 5. Use Fans · 6. Extend the HVAC System to the
One way is to improve your basement air ventilation. Weather permitting, opening up any and all windows or doors can increase airflow and reduce
5 Great Tips For Improving Basement Air Quality · 1. Purify Your Air · 2. Dehumidify Your Air · 3. Remove High “VOC” Contributors · 4. Test For
Stay away from building products that have paper film. Go with metal foil insulation. Instead of wood studs, choose metal studs. Instead of
Also consider a dehumidifier in damp areas, such as a basement, to help prevent the growth of mold. Ensure that bathrooms, another potential source of mold, are