Find out what may be causing hairline cracks in your cinder block walls. Learn how to repair and prevent cracking on your cinder block walls.
LESLIE: Lloyd in Kansas is dealing with some concrete walls that are cracking up. Tell us about the problem.
LLOYD: I have a – it’s actually cinderblock.
LESLIE: (overlapping voices) OK.
TOM: (overlapping voices) OK.
LLOYD: And I’m getting a hairline crack between not all of them but several of them and it goes all the way through so …
TOM: Is it a vertical crack, Lloyd, or is it a horizontal crack?
LLOYD: No, it’s a horizontal.
TOM: And where is it located, say, from …?
LLOYD: It’s right in the mud area, where they …
TOM: Does it seem to be opening though or is it just sort of – like more like expansion and contraction?
LLOYD: Yeah, that’s probably it right there. It’s a little bigger than a hairline crack; some of them are. It’s got several in it and some of them are and some of them are a little wider than others but they’re not real wide.
TOM: Well, look, you might have some movement in that wall that could be causing this and, typically, if you get movement in a concrete block wall, it’s because of a drainage issue
outside. You know, if you have a lot of water that collects around the bottom of the wall, that can contribute to the movement of the wall. And a simple explanation for that is if you walk across your lawn after a rain storm, you kind of sink because wet dirt doesn’t hold as much weight as dry dirt.
And so, if you try to stabilize the soil a little bit, that can cut some of that down. But that said, expansion and contraction is not unusual in a block wall and it’s going to exhibit itself by hairline cracks in the joints and it doesn’t always indicate a structural problem.
LLOYD: OK. Alright. I appreciate it.
TOM: You’re very welcome. Thanks so much for calling us at 888-MONEY-PIT.