How to Clean Mold Off Brick

Brick with mold on it.
  • 4-8 hours
  • Beginner
  • 20-50

It is no fun when mold appears on brick. Mold produces digestive enzymes that eat any surface it is attached to, causing structural damage. If you touch it or inhale the spores, it can cause health problems like asthma, nausea, rashes, or other allergies. As soon as mold appears on your brick, it is important that you remove it. The good thing is, removing mold from brick is a relatively easy thing to do when you follow some simple instructions.

Step 1 - Find the Water Source

Brick with mold on it.

Moisture and water retention are major sources of mold on brick, so finding the water source before you clean is important. If you don’t find it and fix it, the mold will most likely return. There are many different possible problem areas that could be causing water and moisture on your brick, so if you hear water, check these places to find out where it is coming from.

  • Roof: Check your attic for any possible roof leaks and repair any that you find.
  • Walls/Windows: Water can be reaching your brick via leaks in walls and windows. If you find some, use weatherstrip and caulk. If you have window condensation, consider installing insulated glass or storm windows to prevent more problems.
  • Plumbing: Inspect your plumbing pipes for leaks. If you find any, you need to insulate them.
  • Gutters: Make sure your gutters and downspouts are clean, and channel water away from the house to avoid foundation leaks.
  • Basement: Leaks in your basement could be making their way to your brick. Examine your basement and make any necessary repairs.
  • HVAC Units and Ductwork: If your HVAC ducts have excess moisture and condensation that is getting the insulation wet, repair or replace the insulation. You also want to make sure the drains aren’t clogged, and that the HVAC unit is draining properly. Use a high-quality air filter and change it often.
  • Under the House: If you don’t have a basement, check your crawl space for excess moisture, and put black plastic on the ground to reduce the humidity.
  • Bathroom Vent Fans: If you have a bathroom near the outside wall where mold is appearing on brick, install bathroom fans that are vented to the outside. Be sure to run them for a few minutes after showers.
  • Gas Appliances: Gas and kerosene heaters, as well as fireplaces, need to be properly vented to the outside to reduce moisture in the air.
  • Chimney: If you have a brick chimney, inspect it for cracks and debris that could be providing shade and preventing moisture from evaporating.

Step 2 - Take Safety Precautions

Brick with mold on it.

Because mold is dangerous when you touch or inhale it, you have to clean mold with safety in mind. Start by putting on goggles, rubber gloves, and a mask to prevent it from getting on your skin and in your lungs.

Step 3 - Use Vinegar

Brick with mold on it.

Until recently, the recommended treatment to kill mold was a mix of chlorine bleach and water. Now, though, the Environmental Protection Agency says that combination is only effective in killing the mold, but not removing dead mold spores, which can also cause major health problems.

Instead of using bleach and water, pour undiluted vinegar into a spray bottle and spray it on the affected areas. Let it sit for a few minutes before scrubbing it off with a stiff-bristled brush. Next, rinse the vinegar with hot water, and then spray the affected areas again.

After the second spray, you do not need to rinse. Let the vinegar penetrate the bricks so it can kill the mold you can’t see.

There are mold removers that you can purchase from your local home store, like Gone!, Wet and Forget, and Green Envy. But, no matter what you use to remove the mold, it is best to clean your brick when there is low humidity and no chance of rain for at least a day so your cleaning product has time to properly settle.

If you are still having trouble getting rid of your mold and can’t find the water source, you should consider calling a professional to help you fix the problem.

Clean Mold Off Brick FAQ

What kills black mold on brick?

Many home improvement stores sell mold-killing formulas that work on brick but you can also use some fairly common household chemicals to kill black mold the DIY way. Bleach and white vinegar are both effective at killing and cleaning black mold on brick.

Does vinegar damage brick?

Vinegar is strong enough to kill black mold, so it is certainly no gentle chemical. If you put pure vinegar on your brick, it could weaken the material and make it more prone to staining.

However, you can still use vinegar to kill mold on brick. Vinegar should be heavily diluted by a ratio of about three parts water to one part vinegar.

If well-diluted, vinegar can safely kill mold and clean brick.

Is it safe to clean black mold yourself?

The truth is, it is never safe to clean black mold yourself. Mold is dangerous and it releases spores that you don't want to breathe in.

Even professionals are not necessarily safe while treating black mold. However, professionals wear safety gear to mitigate the risk of being around black mold and any DIYer can do the same.

it's very important to wear safety gear while you're cleaning black mold. Always put on gloves to protect your hands, safety glasses, and wear a face mask.

Don't ever remove the face mask when you're working around black mold. Step away from the project add get fresh air any time you need to relieve yourself from the mask.

You should also make sure there is plenty of airflow in the area where you're working. If you're not outside but inside, open as many windows as you can for starters.

You can also use a dehumidifier to remove excess moisture in the air while you're working with black mold indoors.

Will hydrogen peroxide clean bricks?

Hydrogen peroxide is an effective killer of mold on brick, especially when used with baking soda. However, the hydrogen peroxide should be diluted so it will be ae enough for the bricks.

Mix one part hydrogen peroxide with three parts water to get a brick-safe mixture that can kill mold.

What kills black mold permanently?

Existing mold can be killed and cleaned so that no trace of it remains. However, there is no way to prevent mold from ever growing again.

Mold is attracted to moisture, so the best way to keep it from growing is to keep indoor and outdoor areas well-ventilated and dry.