Plumbing rough-in inspection checklist: what Cave Creek inspectors check

The Town publishes a Plumbing Rough Trade checklist on its Building and Fire Code Compliance page, beside separate checklists for under slab plumbing, fuel gas piping and the plumbing final. It is a list to prepare from, written against the 2021 International Residential Code, and the Town now enforces the 2024 codes as amended by Ordinance 2025-08. The lines that fail the most jobs are the tests:

• Drains, waste and vents. "Water tested with a 10' head for 15 minutes or air tested at 5 psi for 15 minutes. Plastic DWV not allowed to be tested with air."
• Water lines. "Tested to working pressure or 50 psi for 15 minutes." Plastic water pipe may not be air tested either, except PEX where its maker calls for an air test.
• CPVC under a slab. A pressure test of 150 psi for two hours.

The rest of the list covers how the pipe is run: no pipe embedded in concrete, Type L copper under ground with brazed joints under a slab, wrapped steel, 18 gauge nail plates where pipe sits within 1 inch of the face of a stud, and plastic pipe supported every 4 feet.

• Rough-in. The pipes inside walls, floors and ceilings, set before drywall and fixtures. Our guide to what plumbing rough-in is walks through the stages.
• 10 foot head. The drain system is plugged and filled with water to 10 feet above the work being tested, and the level must not drop.
• Trap arm. The pipe from a fixture's trap to its vent. Too long and the trap can siphon dry.
• Cleanout. A capped opening that lets a drain be cleared without cutting pipe.

Air is compressible. If a glued plastic joint lets go under air pressure, the stored energy can throw pipe and fittings with real force, and a crew may not see it coming inside a wall. Water does not store that energy, and a leak shows as a wet joint and a falling level. The Town's checklist allows an air test only on drain pipe that is not plastic, so PVC and ABS get water. Plan the water source, test plugs and a way to drain the system before calling for the inspection.

It is a cleanout rule, and Cave Creek's checklist states it twice. A cleanout is required at each horizontal change of direction that adds up to more than 135 degrees. A trap arm 3 inches or larger cannot change direction more than 135 degrees without one, and a trap arm under 3 inches cannot turn more than 90 degrees without one. Each horizontal drain also needs a cleanout at its upper end and one for every 100 feet of run.

Anyone with a plumbing permit inside the Town of Cave Creek: owners building a custom home, owner-builders adding a casita or a bath, remodelers opening walls, and the licensed plumbers they hire. The same checklist applies whether the house is on Town sewer or a septic tank, since the rough-in is the piping inside the building. A lot outside the Town limits gets its permits and inspections from Maricopa County instead, even with a Cave Creek mailing address.

A bathroom remodel. The walls are open, the new shower valve is in and the drain is PVC. The plumber caps the drain, fills the stack to 10 feet and leaves it for the inspector. The checklist also asks for a listed anti scald valve set to 120 degrees at most and a shower at least 30 inches across.

A new custom home on a desert lot. The under slab plumbing was inspected first. At rough-in the inspector looks at the trap arm lengths, the vents through the roof and the water service. Where a metal water service is replaced with plastic, 10 feet of copper stays in the ground on the house side to keep the electrical ground, or the Building Official approves another way.

The edge case. A crew air tests a PVC drain to save time. The Town's checklist does not allow that test on plastic, so plan on filling the drains with water before the inspector arrives.

1. 1Pull the plumbing permit and keep it with the approved plans on site, with the job address posted where it can be seen.
2. 2Finish the rough-in before you call: every fixture drain, vent and supply in place, plates on the studs, supports at 4 feet.
3. 3Set up the tests: water to a 10 foot head on the drains and 50 psi or working pressure on the water lines, held for 15 minutes.
4. 4Book the inspection through the Town's online permitting and inspection portal, and keep the walls open until it passes.
5. 5Keep the job moving. Under Ordinance 2025-08 a permit expires if the work does not pass an inspection within 180 days of the permit, or 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 next stage is the Cave Creek plumbing final inspection.

• "An air test is faster, so it is fine." Not on plastic drain pipe in Cave Creek. Use water.
• "The under slab inspection covered it." The Town keeps under slab, rough and final as separate checklists, each with its own items.
• "The inspector will tell me what is missing." The checklist is public. A failed rough-in means a second visit and a wall that stays open longer.
• "Cave Creek works like Phoenix." Phoenix puts the stages in its code. Cave Creek adds its own checklist on top, with test methods spelled out.