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Basement cinderblock foundation caulking

bud06's picture


We recently bought our first house (built in 1961) from a builder that flipped it. I know they tend to do some things well and skimp on others. After having been in it for a couple weeks now I’ve inevitably begun to notice some items that I had previously missed or overlooked. One question I have given I’ve never had to deal with a basement before is some caulking I came across in the unfinished portion of our basement. The builder we bought it from sealed the cement floor and also put up insulation on the walls so we can’t see a majoritry of them; however I noticed there are sections of thick gray caulking between the floor and cinderblock wall. This wall where the caulking is found is one of the sides that is the furthest underground. About half of this wall has the caulking and the other half doesn’t. 

Should I assume there were prior leaks the builder was trying to cover up? I know with hydrostatic pressure it won’t do much, but can’t think of any other reason. I also saw some sections where there are cracks separating the floor and wall that weren’t caulked, but assume that is from expected settling. I’d love to hear your thoughts and suggestions and also let me know if you think I need to be proactive in addressing something.


You have no way of knowing.  (post #216559, reply #1 of 3)

You have no way of knowing.  All concrete block walls (that aren't heavily reenforced) will crack.  The builder likely felt that caulk looks better than open cracks.

Efflorescence ("chalking") on the wall is a strong sign of seepage, but the builder could have scrubbed this evidence away.  (Check corners where he might not have been real dilligent about scrubbing.)

Of all the preposterous assumptions of humanity over humanity, nothing exceeds most of the criticisms made on the habits of the poor by the well-housed, well-warmed, and well-fed.  --Herman Melville

Thank you much appreciated.  (post #216559, reply #2 of 3)

Thank you much appreciated. 

I would ask the builder you (post #216559, reply #3 of 3)

I would ask the builder you bought it from. Caulk will not keep water out anywhere much less a basement. It's also possible that the crack that is typically there was filled to make the floor and walls look better.

Florida Licensed Building Contractor, 50 years experience in commercial remodeling, new homes, home remodeling and repairs and all types building maintenance.