How to Fix Mildew on a Concrete Block Wall

Mildew is the result of the growth of spores that thrive in damp, poorly lit environments. Concrete block walls that are in shady, damp areas around or on the exterior of your house are susceptible to growth of mildew. Alleviating mildew growth can be addressed by a thorough cleaning using regular household chemicals and tools. This will remove the mildew and inhibit its future growth.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• Broom
• Leaf blower
• Garden hose with spray nozzle
• Garden sprayer
• Bleach
• Water
• Stiff-bristled scrub brush

1. Clean the concrete block wall. Take a stiff broom and vigorously sweep away any dirt or debris that may be on the wall. If you are cleaning an outside wall, a gas or electric leaf blower is an effective tool as well. Using a hose and spray nozzle, spray the wall with water to complete the preliminary cleaning.

2. Mix a solution of equal parts household bleach and water in a household or garden sprayer. Close the lid and pressurize the pump by pumping the handle until you can spray a steady mist from the spray nozzle.

3. Spray an area of the concrete block wall with the sprayer's solution. A square about 2 feet by 2 feet in size is a good size.

4. Scrub the area you have sprayed with a stiff-bristled brush until the mildew is removed. In areas with thick mildew, you may have to repeat this process. Rinse the brush frequently with your garden hose. Spray off the area you have scrubbed with the hose. Continue working on the wall until you have completed the entire area.

5. Use your leaf blower to blow dry the wall when you've completed the job.

Tips & Warnings

• If bleach irritates your skin, wear rubber gloves.

References

• Cleaning Plain & Simple: A Ready Reference Guide with Hundreds of Sparkling Solutions to Your Everyday Cleaning Challenges; Donna Smallin; 2005.