Dealing with Black Mold Prior to Painting

What is Black Mold?

Black mold can form on any surface when there is moisture present, and can potentially be lethal to humans-especially babies-and animals as well. If you live in an area that consistently has high humidity, then there is always the potential for having mold issues. Any humidity level above 55% will promote mold growth. Mold issues can also arise from leaky water pipes which have gone undetected or flooding. Your first sign of a potential mold problem can be smell, since normally mold will grow in places you are unlikely to see. However, if your nose consistently detects a mildew-y smell, then you would be wise to look for signs of mold or call in a professional. Basements and crawl spaces consistently receive less ventilation that other parts of the house, and also commonly have cooler temperatures which in turn lead to higher humidity levels. If you've noticed yellowing stains on your walls or ceilings, then this is a sure sign of moisture. In cases where the mold is already in the full-blown stage, you may see green, brown or black discolorations, or may notice places where the paint is coming off because of the excessive moisture levels.

Health Consequences of Black Mold

Humans can have a wide array of negative response to mold, depending on the type of mold present as well as the extent to which it has spread. Exposure to mold can come through skin contact, and inhaling or ingesting mold-spore saturated air. Allergic reactions, skin irritations and more serious respiratory diseases are all possible when mold is present.

Once You Have Discovered the Source

Once the source of the mold has been identified, you will need to thoroughly clean the area prior to painting. It's never a good idea to paint over mold. The spores remain, along with the health threat, and although it may look prettier, the underlying problem remains. If you only have a small amount of mold present, add a cup of bleach to a gallon of water, and thoroughly scrub the area in order to disinfect it. Once you have completely scrubbed the area, allow it to dry completely, then go over it with a fine-tooth comb to make sure the mold has all been removed. Before you purchase your paint, go to your home improvement center and ask someone in the paint department about adding a mold inhibitor to your paint.


If your mold problem was rather extensive, then you should probably have a mold inhibitor added to your primer as well. Mildew inhibitors prevent the growth of new mold and mildew, but do not destroy existing mold, so make sure you have applied the bleach solution completely and removed all present mold. Remember that paint or primer which contains linseed oil will be much more likely to mildew as will paints that are lower quality. Water-based paints with a flat or eggshell finish are more likely to mildew, while the glossier latex paints or latex enamel paints are much less porous, prohibiting the mold spores from "grabbing on." Once you have cleaned, primed and painted your surface, make sure to keep the painted surfaces very clean in the future; grease in the kitchen as well as soapy scum, are perfect breeding grounds for future mold and mildew. Control the moisture levels in your home; even having a surplus of plants in your home can add too much humidity to the air, causing future mold problems. Make sure your house is adequately insulated as dampness can occur when warmer air comes in contact with a wall which is insufficiently insulated. Finally, use exhaust fans which are properly vented to the outside, and check to make sure your dryer vent is installed properly. Once you've removed the mold and painted your home, be extra-vigilant in watching for future potential signs of mold.