Tommy Mac Discussions › Forums › Fix-it Forum: Home Improvement & Do It Yourself Repair Forum › Crack in new concrete patio slab › Yep, Hair line cracks wiill happen.
I had a slab installed going the whole width of the house in the back.I told them that on the center 1/3 of the slab I would later build a room and that the thirds on either side would be patio. In the center he installed 22 inch footings against the house slab and around where the room would be. The patio portions were 4 inches thick. The center has no cracks but the two patio portions have hairline cracks.