Crack in unstressed slab?

Question

We are having a new home built in a Houston suburb. The slab is post-tension, but has not been stressed yet (poured 8/13). Walking the house yesterday I found a crack that runs across the entire slab and is all the way down through the thickness of the slab on both sides. We called the builder and he said this is not uncharacteristic, and the crack will disappear when the cables are stressed. We went to the website of a large Houston post-tension company and found this confirmed but want to know if anyone has first-hand experience with this to reassure us.

Answer 1

Cement dries and shrinks and will ultimately crack. That is a large piece of cement and it will crack somewhere. If you notice that it is shearing (one side higher than the other) or the crack is in excess of a certain amount of inches (should be recorded in your local code) then you should push your guy a little more. Just make sure you have it documented that you advised the contractor and he replied to you in case something does perchance happen later on as that would be major structural. Document document document...