Plumbing systems and drains cost homeowners time and money more than any other source of water loss. It only takes a small amount of water soaking into floors, walls or cabinets from a faulty pipe, or bubbling up from a backed-up sewer drain to cause thousands of dollars in damage to your home or business. An IBHS study of closed water damage insurance claims identified plumbing pipes and drain systems as leading causes of interior water damage.