Cinder block shedding its skin

Old 11-25-15, 04:05 PM
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Cinder block shedding its skin

We live in the eastern Colorado plains. Our house was built in 1956. It is a split level. There is an entry area at ground level and then you go up 7 steps to the upper floor or you go down 9 steps to the lower floor. The exterior walls of the lower floor are cinder block with a coat on the inside that reminds me of stucco. This inside coat is painted. In one of the rooms, the stucco looking coat is peeling off of the cinder block. The cinder block feels damp. I do not know if the dampness is coming from the outside (seepage) or from the inside (condensation).

How do I repair this? Do I put on a coating of stucco? Do I put on a coating of fortified thinset? Do I prep it first? Help.
Old 11-25-15, 05:20 PM
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A picture may help. More likely it's parging, Google it.
If the walls are wet then 99% of the time it's coming from outside.
Could be dozens of things causing it.
No waterproofing on the foundation.
No gutters.
Mulch piled up against the foundation.
Landscape timbers forming ponds.
No slope in the grade away from the house.
There just is no magic coating you can apply to the inside of the walls to water proof.
Old 11-26-15, 04:24 AM
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What little bit I know about parging leads me to believe it's the same as stucco. Up to a few yrs ago I never heard of parging but I've painted miles of stucco applied to block over the last 40+ yrs.

What is the humidity level in the basement? do you run a dehumidifier? While basements are often humid it's most likely the moisture affecting the walls came from outside

Is the exterior side of the block stucco'd? or painted? Bare porous block is apt to let moisture pass thru it although the most important area is what's below grade. Coatings like Drylok applied to the interior side of the foundation help a little BUT are never a substitute for waterproofing done on the exterior! Also drylok requires bare masonry to be applied to. The moisture issue needs to be addressed first, then you can worry about fixing the interior coating to make it blend.
Old 11-28-15, 05:01 AM
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The house has a metal roof. The pitch of the roof is 12:12 (45 degrees from the horizon). The eaves are about 28 inches above the ground. There are no gutters. The water running off the roof hits the ground about 7 inches from the outside of the walls. We usually don't get much precipitation. We had an exceptionally wet spring last year. It sounds like I need 45 feet of gutter on each side of the house to keep the water away from the walls.
Old 11-30-15, 09:06 AM
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Step one is address the outside - move water away from the walls with gutters, downspout extensions and grading. Sometimes this is easier said than done and so people try to paint the inside wall instead but trying to stop the water when it's already 99% of the way through usually accomplishes little.

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