Faulty plumbing can result in serious health and safety hazards such as noxious gas backups, back siphoning, bursting pipes, floods or electrical shorts. To see that these standards are adhered to, we have plumbing codes and permits. Materials are of great controversy and are constantly being updated. Some areas may require insulating your water pipes or puffing vacuum breakers on your outside hose bibbs. The list can go on and on.
All areas are different and change quite often.
Before beginning any work, be sure your plans conform to ALL local codes and ordinances. Discuss your plan's with the local building inspector and obtain the necessary permits at the same time. Find out what work you may do yourself and what must be done by a licensed plumber. Be certain to follow these codes to the letter or you will run the risk of having to rip out all of your hard work. Your plumbing work may require inspections at several different stages from the rough to the finished work.