How to Remove Mildew from Sheetrock

Last Updated: March 22, 2023

When Sheetrock is exposed to moisture mildew can begin to grow on it almost immediately. To remove the mildew, the problem with the moisture must be corrected first, then try these simple steps.

Steps

1
Remove the source of moisture which is supporting the mildew before trying to remove the mildew. If it is a wall or roof leak, patch or repair it. If it is simply condensation, like moisture in a bathroom or shower, you may need a ventilation to remove humidity from the room.^{[1]
X
Trustworthy Source
Federal Emergency Management Agency
Federal agency responsible for coordinating responses to disasters and states of emergency
Go to source}
2
Prepare a solution of one cup chlorine bleach with water to make one gallon.^{[2]
X
Research source}

Advertisement
3
Pour your solution in a spray bottle. This can be the type used for misting plants, or a used cleaning product bottle which has been thoroughly rinsed.
4
Provide fresh air in the room or area you are working before proceeding.^{[3]
X
Trustworthy Source
Centers for Disease Control and Prevention
Main public health institute for the US, run by the Dept. of Health and Human Services
Go to source}
5
Spray the area that has mildew showing on it sufficiently to dampen it, without excess liquid running off the surface.^{[4]
X
Research source}
6
Allow the area to dry, and brush any loose mildew off with a dust rag or dry towel.
7
Repeat if the stain does not disappear with your first attempt.
8
Before painting, use a "stain-blocker" primer/sealer paint suitable for use under your finished coat. If the area is going to be exposed to high humidity or moisture often, use an oil based alkyd enamel with a gloss finish. This paint is more mildew and moisture resistant than most latex paints.^{[5]
X
Research source}

Community Q&A

Question

Does bleach kill the mildew or just bleach the spores?

Community Answer

Bleach will kill the mildew.

Warnings

Do not breathe concentrated vapors from chlorine bleach

⧼thumbs_response⧽
Helpful 6 Not Helpful 2
Avoid spilling or splashing chlorine bleach on your clothing or skin.

⧼thumbs_response⧽
Helpful 5 Not Helpful 4
Put the chlorine solution in clean containers only, and dispose of the unused portion when you are finished.

⧼thumbs_response⧽
Helpful 3 Not Helpful 2