A plumbing permit is required to do the following:
Replace water heaters, alter piping inside a wall or ceiling or beneath a floor, and for plumbing in all new installations.
Repair, alteration, or replacement of freeze-damaged or leaking concealed piping, if new piping exceeds 3 feet.
Remodeling or adding on to your one or two family dwelling when existing plumbing is to be relocated. This includes installation of building sewers, water service, and exterior rain drains.