About a year ago (last Spring) I bought 1994 colonial in Massachusetts. Several cracks (1/8" wide x 6 to 15 feet each) have just appeared in the concrete basement floor. The cracks are originating from one area. There are no cracks in the foundation. I know that cracking is normal, but thought that this usually happens soon after construction, not 17 years later. The basement doesn't and never had any water leakage problems. I'm also sure that large cracks were not there before; the basement is/was not finished and there is no covering/paint on the floor. Although, it's possible there may have been some hair-line cracks that weren't noticed. The cracks appears some time in the last month. We did/do have a dehumidifier running since June. I don't think the previous owner ever used a dehumidifier, but the dehumidifier really doesn't turn on too in the Winter (when the cracks appeared). It has been a cold/icy winter with the basement temperature now at 50 degrees. Also there had been extra weight on the roof recently do to a lot of snow.
Is it just random chance that the cracks just appeared now after 17 years?
Is the dehumidifier or snow on the roof a cause?
Is this a sign of something worse?