I would check the ceiling below for leveling. Seems like that would tell you if it was structural. Also cracks in paint, seams. Assuming it's structural if it's that noticeable. I know for flooring it should be level within 3/16th of an inch which is really not noticeable. Have you put a level on it? If it's an inch or more something is likely going on either with lateral bracing or the foundation. Â
@beastmode:
Good points - also, I would add that since it is the second floor it could be just problems with the subfloor and could be fixable, although they would have to remove at least some of the wood floor to get to it. 4951