I had a concrete driveway poured one year ago, and it has developed cracks in between the seam joints. The actual pad is not cracked, just in the depression between the pads. I assume this is not a good thing and something should be done, like caulk or sealant to prevent water, and around here, ice from making them worse. The largest crack is about 1/8 wide. Is this something I should take up with the contractor on the job to repair or make good on?
Pete ~ Akron, Ohio
Hi Pete, If your concrete driveway is cracking at the joints and there are no cracks anywhere else, then your contractor did a good job when he prepped and poured your driveway.
All concrete is going to move after it is in place for awhile; this is due to expansion and contraction from the climate and also the earth moving below the concrete and this movement is going to cause the concrete to crack. If you're ever in a large commercial warehouse that has an expansive concrete floor, walk around and look at the floor. You should see various places where it looks like the concrete has been cut and that's because it has. A day or so after the concrete cured the contractor used a walk behind saw to cut joints in the floor to allow room for expansion and contraction.
You can even see the same thing in large homes that have a big unfinished basement. The contractor will often cut a joint from pipe column to pipe column so that the basement looks like a series of squares. These are called control joints in the business and that's exactly what the joints are in your driveway as they give the concrete a place to have a controlled crack rather than a large diagonal crack across the drive. The joints also make it convenient if you ever have to replace a section of your concrete driveway; you just have to replace a section between joints rather than the whole driveway or a section that looks like a patch job.
You can purchase concrete caulk at most home improvement stores; just put a good bead of caulk along the crack to prevent water from going down there. You are absolutely correct that you don't want water to get down there and freeze or you may have lots of cracks and the sections of your concrete driveway may soon be at different heights. I grew up in Pittsburgh so I know how cold it can get in Akron, Ohio during the winter. Check the caulk at least once a year and it wouldn't hurt to check it in both the spring and fall. I would also check all your other control joints because if they haven't cracked yet, they soon will be.