Published on March 17th, 2016 | by Henri0
Waterproofing a basement with poured concrete walls
Q. I was reading in your recent column about not painting basement concrete walls with waterproofing paint. Great, but what do you do to correct basement walls that have been painted with waterproof paint? Can you get the paint off and will this correct the problem? How do you correct this problem? My walls are clearly starting to get mold on them in one corner. The outside has been graded on three sides. Inside there is a drain three inches from the wall carrying water to a pump. This is a mess. How do I solve it?
A. I was not referring to poured-concrete basement walls but to concrete block walls. If your foundation walls are made of poured concrete, there is no reason why they should not be painted with whatever will stick on them. However, if the walls are built with concrete blocks, they should not be painted with waterproof paint unless some provision is made at their base for water that might penetrate from outside to drain inside into some disposal system.
If your basement is leaking, that should be investigated. It may be that the fourth side of the house needs to be regraded as well. It is also possible that the mold that develops in one corner is caused by summer dampness and condensation of ambient air on the cold surfaces found in those low corners. If you open windows in the summer to ventilate the basement, try not to do so in the future, and use a dehumidifier instead. Outside warm, humid air – when allowed into a basement — will condense on walls that are kept cool by their contact with the earth, and the deeper the walls are in the ground, the cooler they remain.by