How to Remove Mold From Concrete Basement Walls

concrete wall with black mold
  • 2-4 hours
  • Beginner
  • 0-100
What You'll Need
Warm water
Mild soap
Empty spray bottle
Breathing mask
Protective gloves
Protective eye wear
Hard bristle brush
Clean cloth
What You'll Need
Warm water
Mild soap
Empty spray bottle
Breathing mask
Protective gloves
Protective eye wear
Hard bristle brush
Clean cloth

Nobody wants mold in their homes. In addition to being quite unsightly to look at, some types of mold can also have negative health effects when people are exposed to it for long periods of time.

If your concrete basement walls have recently fallen victim to a mold infestation, you may be wondering how to go about getting rid of said mold infestation before it spreads and creates havoc in your basement. Below are the necessary steps to remove such an infestation from your home.

1. Clean Your Basement Walls

Like many DIY projects, the first step here is simply to clean. Before you can begin the mold removal process, you must give your concrete basement walls a thorough cleaning.

You should begin this step by combining warm water with a mild brand of soap in a bucket or bowl that you are capable of lifting. Mix it thoroughly. How much cleaning solution you need will depend on how big the moldy section of your concrete wall is.

Next, pour the newly formed cleaning solution into an empty spray bottle and proceed to vigorously apply it to your mold-laden basement walls.

You will now need to use a sponge or a scrub brush to wipe the walls clean, taking care to fully purge any caked-on dirt deposits.

Any remaining dirt or debris stands to cause problems when the mold removal process is underway, so when performing this step, take your time. This may seem like a silly first step but it is actually incredibly important.

Once your walls have been sufficiently cleaned, you'll be ready to move on.

2. Apply Bleach to the Concrete Walls Infected by Mold

Now that your concrete basement wall is nice and clean, you are ready to begin removing the wall-based mold. To start, fill a clean bucket with one cup of bleach and one gallon of warm water. Mix the two together thoroughly.

As many people find the potent fumes emitted by commercial bleach to be overpowering, it is important to take the proper precautions when working with your bleach mixture.

Before beginning to use the bleach mixture for mold removal, put on a breathing mask, protective eyewear, and a pair of protective gloves. This will protect you from the bleach fumes.

In addition, make sure to perform the job in a well-ventilated area and make a point of taking breaks, preferably outdoors, in the event that you feel yourself becoming lightheaded.

If the moldy walls are not in a well-ventilated area, run a ceiling fan or bring a stand fan into the area that you run during the length of the project in order to create ventilation.

Like cleaning, this may seem like a silly thing to do, but ventilating the area and wearing protective equipment are both necessary as you take on this project and will protect you in the long run as bleach fumes can be really bad for you, your family, and your pets.

Make sure small pets and young children are not in the area where you are working.

You will now need to use a hard bristle brush to vigorously apply your homemade, bleach-based mold remover to any mold-infected areas of your wall.

Wall-based mold can be quite stubborn, so it may be necessary for you to put forth a steady amount of elbow grease.

Depending on the size and severity of the mold deposits on your basement wall or walls, this process may take anywhere from several minutes to several hours to successfully complete.

After the mold has been scrubbed off your concrete walls, allow your mold remover to sit for 15 to 20 minutes before proceeding to dry your walls. This will give it a chance to really sink in and do its job properly, leaving your walls free of mold in the future.

3. Apply Your Finishing Touches

Having rid your basement walls of mold in the previous step, you are almost finished. You will now need to fully dry the freshly cleaned walls with the aid of a clean cloth. When performing this final step, take care to be as thorough as possible.

Dampness and moisture are among the leading causes of mold formation, so it is in your best interest to keep your basement walls completely dry at all times.

After drying off your walls, make sure that your basement receives proper ventilation and that its humidity levels are kept firmly in check.

Additionally, be sure to periodically check your basement's pipe fixtures for any signs of leakage. These precautionary measures will go a long way in keeping your basement's walls mold-free.

Why Does Mold Grow in Basements?

If you have repeated issues with mold growing on the walls in your basement, you may be wondering why mold infestations keep happening in your home.

Basement mold, like all mold, likes moisture. Any leaks in your foundation or standing water that has gone unnoticed are both frequent culprits of mold growth in basements.

Mold can, however, grow without water being present in your basement. Humid air and dark or damp conditions can also cause mold to grow in your basement.

Does Vinegar Kill Mold on Basement Walls?

You may be wondering if something other than bleach will work to kill the mold on your basement walls.

Vinegar, which many people have on hand already for other cleaning projects, works well to kill mold on basement walls. So well, in fact, that it is becoming the preferred method of mold removal for many.

Vinegar does not have as strong a smell as bleach and is often something people already have in their homes, which makes vinegar a great option for removing mold from a concrete basement wall.

Vinegar does not, however, kill all types of mold from basements, but it can clean a large percentage of the mold you will find in your home. To use vinegar to kill mold, you will need to start by cleaning the walls in your basement, just as you did when using the bleach method.

Start by combining warm water with a mild brand of soap. Combine it thoroughly. How much cleaning solution you need will depend on how big the moldy section of your concrete wall is.

Now it is time to pour the newly formed cleaning solution into an empty spray bottle.

Apply it to your mold-laden basement walls and use a sponge or a scrub brush to wipe the walls clean, taking care to fully purge any caked-on dirt deposits. Any remaining dirt or debris stands to cause problems later on.

Next, put your vinegar in a spray bottle. It is best to use cleaning vinegar, which is more acidic than other types of vinegar. Using a spray bottle, spray vinegar on the moldy area in your basement. Let the vinegar sit for an hour.

After the vinegar has had time to soak, you will be able to scrub off the mold, Make sure to do so thoroughly and ensure that there are not stubborn mold deposits left on your basement walls.

After you are done with this, grab a clean cloth and dry the basement walls. This will help prevent mold from growing again in the spot where you just removed the mold because, as previously mentioned, mold loves moisture.

Do not let your wall become a target where it grows regularly.

How to Prevent Mold on Concrete Basement Walls?

You may be wondering how to prevent mold from growing on your concrete basement walls in the future. As previously mentioned, mold loves moisture, so the best way to prevent it from growing in your home is to get rid of excessive levels of moisture and standing water.

If there are any foundation cracks, leaky pipes, or unsealed windows in your basement, make sure to address these issues immediately.

You may want to turn to the pros for these issues, especially foundation cracks, as they are difficult to fix yourself.

Fixing these issues will make it difficult for water and moisture to find ways into your basement and therefore make it difficult for mold to form on your concrete basement walls.

You should also check your sump pump. A sump pump's job is to move water away from your home. If it is not working, however, it can cause flooding in your basement and home.

Since mold loves water, a faulty sump pump can result in mold growth in your home. Make sure to check on your sump pump periodically, and do not ignore it until issues arise. It may need some occasional maintenance work.

Another way to prevent mold growth is by using a dehumidifier. A dehumidifier takes water out of the air and reduces the moisture level where they are sitting. As a result, dehumidifiers can help prevent mold and mildew from growing in your basement walls.

You should also be careful about what flooring materials you use in your basement. Carpet can hold on to water and moisture in a way that vinyl, for example, does not.

While carpet may seem like a good choice for a basement because of its price point, other materials are better for fighting against mold growth.

Most of all, you should keep the space clean. A cluttered space has less circulation and makes it more difficult to spot issues with mold early on.

White Mold in Basement Walls

White mold can, as its name suggests, appear white. It can also, however, look green or grey. It has a powdery appearance. White mold is one of the more common types of mold found in basements and likes to grow in areas with a lot of moisture.

While white mold may be seen by some as less problematic than its black counterpart, white mold can also cause health risks if left untreated for a long period of time.

Black Mold in Basements

Black mold is another type of mold you may find in basements and other areas with a lot of moisture. Black mold is incredibly bad for you and can cause allergic reactions and even lung irritation and issues. It can also cause coughing and sneezing and irritate your eyes.

Black mold is often referred to as toxic mold. As such, it should be dealt with immediately.

Like other types of mold, black mold grows in areas with lots of moisture and water, meaning keeping areas dry and well-circulated are two great ways to prevent black mold from growing on your basement walls once you have gotten rid of the initial infestation.


Make sure you remove mold as soon as you see it. Some types of mold may solely be an eyesore. Other types of mold can be quite dangerous and have negative health impacts on you, your pets, your family, and your friends.

The above-mentioned mold removal method uses bleach to rid your concrete wall of mold. Since bleach has a strong odor, it is important to ventilate the area using fans if there is no natural ventilation, take breaks, and wear protective equipment.

Once you have gotten rid of the mold, make sure to take the tips above to prevent mold from returning to your basement and your life. Mold loves damp, dark places, which is why basements are a frequent haunt for mold-covered walls.

Mold also spreads. So getting rid of mold when there's only a small amount of it should always be the goal. Do not let the mold continue to spread. Make sure to check yours regularly and prevent mold from taking hold in your home.

If the mold issue is severe, you may want to call in professionals to deal with the problem, or at the very least, rent professional equipment to get rid of the mold and protective equipment to protect you in the process of eliminating the mold from your home.