I'm ready to put a bid in a 100 year old home that has a terra cotta roof. They are not flat tiles but rather rounded, as if I had a cylinder and cut it in half. I have been looking for someone to inspect it and no one knows anything about them. How long do these roofs last?? What is underneath the terra cotta?? How can I determine it's integrity?? Are there any sites anyone knows of that I can read up on these? I have looked but haven't come up with much.