Published on January 13th, 2013 | by Henri0
Crack in a concrete floor
Q. Our house was built two years ago. The concrete floor in our unfinished basement has a large crack across it, approximately 1/8 of an inch wide. Is this something that I should be worried about? Is there something we should be doing to seal the floor. We do not get water or anything coming up the crack.
A. If the crack is straight, it may be following a control joint. This is a common practice in large expanses of concrete to allow for shrinkage that occurs as concrete cures. This should not be of concern unless the concrete shows vertical displacement (one side of the crack is materially higher than the other).
If the crack is irregular, it may also be due to shrinkage during the curing process because no curing agent or other shrinkage control was used – and no control joints were included as they should be in any expanse larger than 20 feet by 20 feet.
Again, if there is no vertical displacement this should be of no concern, but the crack should be filled with a concrete slurry.
If there is material vertical displacement (more than 1/8th of an inch), you may want to have a contractor look at it to determine if there is a substantial settling problem.by