Plumbing final inspection checklist: what Cave Creek inspectors check

The Town of Cave Creek posts a Plumbing Final checklist on its Building and Fire Code Compliance page, beside the under slab, rough trade and fuel gas checklists. It is written against the 2021 International Residential Code, and the Town now enforces the 2024 codes as amended by Ordinance 2025-08. It falls into six groups:

• Permits and plans. The address posted where it can be seen, the permit and approved plans on site, and every fixture listed on an over the counter or e-permit. A separate sewer or septic permit must already be signed off, and the water service and storm drainage inspected.
• Notes from earlier inspections. An air admittance valve set at rough-in needs its grille, and shock arresters flagged at rough-in must be in.
• Backflow. An irrigation system needs a backflow device signed off. A home with fire sprinklers needs backflow protection unless it uses an approved combination system, and a water line to a hydronic boiler needs a reduced pressure backflow preventer or an air gap.
• Vents and hose bibs. Vents at least 6 inches above the roof and 10 feet from or 3 feet above an opening window, with no test plugs left in them. Hose bib pressure at 80 psi or less, or a pressure reducing valve goes in.
• Water heaters. The relief valve, its drain, the pan, garage height, vehicle protection and expansion control, set out below.
• Fixtures, dishwashers and insulation. Leaks, water temperature, valve handing, clearances, the dishwasher air gap, and insulation on pipes in unheated spaces.

The Town splits them. A gas water heater swapped in with no change to the piping is a mechanical inspection on the Residential Mechanical Final checklist. An electric water heater, or a gas one where the pipes were changed, gets the plumbing final. Either way the same rules for the relief drain apply. HQ's water heater service covers both kinds.

The temperature and pressure relief valve goes where its maker says, usually in the top 6 inches of the tank. The drain from it must:

• have an air gap and drain by gravity, with no trap anywhere along it;
• be pipe listed for 100 psi at 180 degrees, no smaller than the valve's outlet;
• end outside the building 6 to 24 inches above grade, with a glued or soldered elbow pointing it down, or at an approved drain;
• never connect straight to the sewer, and never end in a threaded fitting.

A retrofit heater with no relief drain to reuse may discharge 6 to 24 inches off the floor.

Only in two cases, by the Town's checklist: when pressure in the public main is over 120 psi, or when the house is on a closed system. A closed system is one with a check valve, a backflow preventer or a pressure regulating valve on the line, because water heated in the tank can no longer push back into the main. Many homes have a pressure reducing valve, so check for one before you assume no tank is needed. Our guide to whether you need an expansion tank explains how one works.

• Air gap. Open air between a drain pipe and whatever catches it, so dirty water cannot be drawn back up the pipe.
• Closed system. A water line with a one way device on it, so water cannot flow back toward the street.
• Trap primer. A valve that adds water to a floor drain trap so it does not dry out and let sewer gas in.
• Flammable vapor ignition resistant. A gas water heater built so fumes on a garage floor cannot reach its flame.

Anyone closing out a plumbing permit inside the Town of Cave Creek: owners finishing a custom home, owner-builders adding a casita or a bath, remodelers, and the licensed plumbers they hire, plus anyone replacing an electric water heater. The checklist applies on Town sewer and on septic, though a septic system has its own permit that must be signed off first. A lot outside the Town limits gets its permits and inspections from Maricopa County instead, even with a Cave Creek mailing address.

An electric water heater in a garage. The plumber replaces a failed electric heater. That is a plumbing final, not a mechanical one. The inspector checks the relief drain runs downhill to the outside wall and ends with an elbow between 6 and 24 inches off the ground, and that a bollard or wheel stop keeps the car off it.

A new custom home on a desert lot. The house has a pressure reducing valve at the water service, so it is a closed system and needs an expansion tank. The inspector also tests a hose bib for pressure, runs the showers to check the water stays at or under 120 degrees, and looks for an air gap on the dishwasher.

The edge case. A soaking tub is set with the hot handle on the right as seen from the deck. The checklist puts it on the left as seen from inside the tub, so it fails and the valve is turned around.

1. 1Read your earlier inspection notes and finish every item they flagged, such as an air admittance valve grille or shock arresters.
2. 2Make sure any separate sewer or septic permit, the water service and any backflow device are signed off first.
3. 3Walk the job with the Town's checklist: run every fixture, test a hose bib for pressure and check the hot water temperature.
4. 4Check the water heater from top to bottom: the relief valve, the drain and where it ends, the pan, the height and the expansion tank.
5. 5Book the final through the Town's online permitting and inspection portal. Under Ordinance 2025-08 a permit expires if the work stops passing inspections for 180 days, and restarting it costs one half of a new permit.

HQ Plumbing & Air serves homes in Cave Creek. See residential plumbing or our Cave Creek service area page. The stage before this one is the Cave Creek rough-in inspection.

• "Every water heater needs an expansion tank." Not by the Town's checklist. It is only over 120 psi in the main or on a closed system.
• "The relief drain can run to the nearest drain line." It may not connect straight to the sewer. It ends outside or at an approved drain.
• "A gas water heater swap is a plumbing final." Only when the pipes change. Otherwise it is a mechanical inspection.
• "The final is only about fixtures." The Town also checks backflow devices, roof vents, hose bib pressure and pipe insulation.