# New concrete patio has hairline cracks throughout-what are my options?



## jomama45 (Nov 13, 2008)

The concrete guy should know, without a doubt, if it was a "hot load". For someone who does it for a living, there's not much "grey area" in this part of it.

I'd let it sit at least a month, longer would be better, to ensure that it's done shrinking before installing a wet-set flagstone over the top of it. If it's going to fail structurally, it's best to let it sit through a winter (assuming you're in a cold climate that sees freezing) to put it to the test.

W/o seeing the patio, it's relatively hard to troubleshoot though.......


----------



## Canarywood1 (May 5, 2012)

I agree with jomama45,if it was a "hot load" he should have known and rejected it,although there are other reasons for hairline cracks to appear,soil compaction and weather being two of many.

by the sun which causes faster evaporation of the concrete water contents. The rapid drying of concrete causes the concrete composition to contract early in the curing process, causing hairline cracks. Additionally. this concrete dries quicker on the surface than at the core. The differences in drying and expansion and contraction will almost always yield hairline cracks.


----------



## Tina1112 (Oct 1, 2012)

Thanks JoMama and CanaryWood for responding.


----------



## Mort (Nov 26, 2008)

This normally happens when a contractor tries to do two things. The first is order the concrete with a lot of accelerator so he isn't there all day, and the second is add a lot of water so it's easier to work with. I can't say this is what happened for sure, but I'm guessing it was. All the water he probably added will increase the shrinkage, thereby causing the spider cracks.


----------

