General Administration and Plumbing Plan Review Fundamentals
Scope and permit triggers
The administrative provisions set the rules of the game: the code official's authority to approve or reject, the work exempt from permit, what must be submitted for review, and how inspections are sequenced. A permit is required for new installation, extension, alteration, or replacement of piping and for fixtures newly connected to the system. Ordinary repairs - clearing a stoppage, replacing a faucet washer, re-caulking a joint - are exempt. Replacing a water heater or rerouting a drain is permit work.
Plan review fundamentals
A plumbing submittal typically must show floor plans, a riser diagram or isometric, a fixture schedule with drainage and water-supply fixture-unit loads, pipe sizes and materials, slopes, and the sizing method used. The reviewer checks minimum fixture counts against the facilities table, trap and vent adequacy, backflow protection, and separation of water and sewer lines. Concealed work must be inspected before it is covered, and the permit holder requests the inspection.
Traps in questions
- "Approved" (acceptable to the code official) is not the same as "listed and labeled" (third-party certified). Distractors swap them.
- Existing structures: the code applies to new work and to alterations, but generally does not force a full upgrade of untouched systems.
- Alternate materials need a written request with supporting evidence, not just a manufacturer's brochure.
- Work begun before permit issuance is a violation even if the installation is code-compliant.
Rule of thumb
If the work adds, extends, replaces, or reconnects pipe or a fixture, a permit is needed. If it restores an existing fixture to working order without changing the system, it is a repair.