How to Kill Mold on a Concrete Floor

Hunker may earn compensation through affiliate links in this story.

Things You'll Need

  • Spray bottle

  • Stiff scrub brush

  • Bucket

  • Non-ammonia dish soap

  • Rags

  • Chlorine bleach


Never mix bleach and ammonia, or products containing these ingredients. The results could be toxic. Wear rubber gloves, protective eye and face wear and clothing that covers your arms and legs during mold removal. This will protect you from the mold, as well as from the cleaning agents.

Preserve the appearance of your concrete floor by killing mold promptly.

Mold is a fungus that thrives in damp environments. It is not uncommon for mold to form on a concrete basement floor. Removing concrete mold is important in preserving the health of those living and/or working in the area where the mold is present. Mold can have adverse health effects through excessive exposure. Protect yourself and those around you by killing concrete mold promptly.


Video of the Day

Step 1

Moisten the concrete floor with water prior to mold removal. Removing mold from a slightly damp floor will reduce the amount of mold spores released into the air during removal. Use a spray bottle filled with water to lightly mist the moldy concrete.

Step 2

Scrub the molded concrete with a stiff scrub brush. This will loosen up some of the mold to make cleaning easier.

Step 3

Fill a bucket with warm water. Add a few squirts of non-ammonia dish soap to the water. Stir the mixture up with your hands to thoroughly combine the soap and water.


Step 4

Dip a scrub brush into the bucket of water. Scrub the molded concrete with the scrub brush and soapy water. Rinse out the scrub brush often while cleaning and change the bucket of soapy water periodically to avoid reapplying mold to the surface.

Step 5

Discard the soapy water and rinse out the bucket thoroughly to remove all traces of soap. Fill the bucket with plain, warm water.

Step 6

Rinse the concrete floor with rags and the plain water. Change the bucket of rinse water once it becomes soiled or soapy.


Step 7

Discard the rinse water and rinse out the bucket well. Fill the bucket with a chlorine bleach and water solution. Use ½ cup chlorine bleach for each gallon of warm water.

Step 8

Scrub the bleach solution onto the concrete floor using a clean scrub brush. Allow the bleach solution to sit on the floor for 15 minutes.

Step 9

Discard the bleach and water solution and thoroughly rinse out the bucket. Fill the bucket with plain, warm water.

Step 10

Rinse the concrete floor with clean rags and the plain water. Dry the concrete floor promptly. Use towels to soak up excess water. Place fans and dehumidifiers in the room, if possible, to speed up the drying process. Open doors, windows and turn on ceiling fans as well.



Kimbry Parker

Kimbry Parker has been writing since 1998 and has published content on various websites. Parker has experience writing on a variety of topics such as health, parenting, home improvement and decorating. She is a graduate of Purdue University with a Bachelor of Arts in organizational communication.