I moved into a brand new house in July, the house was finished in June. I have just noticed that I have new cracks on my basement floor, although I have no water coming through. I live in the northeast and the ground around me is rocky and I have water drained from the house fairly well. What would cause this?? How do I fix it so it doesn't happen again? The house is just 6 months old. Would the builder be somewhat responsible?