Stage 05 · 4 sheets

Plumbing Trim-Out and the Final

Plumbing trim-out is the finish stage: once walls, tile and floors are done, a licensed plumber sets fixtures, faucets, stops and shower trims, then the final inspection closes the permit.

Set by the Trench to Trim desk from code, agency and maker documents · how pages are made · Updated October 28, 2026

A newly set white vanity sink with a brushed nickel faucet over a dark cabinet, mirror above

Proof marks

The 2021 IPC section 108.2 makes the final the third required plumbing inspection, after underground and rough-in.
Shower and tub-shower valves must be pressure-balance, thermostatic or combination types with a limit stop set to no more than 120°F under the 2021 IPC and the 2024 UPC.
The CPSC says most adults get third-degree burns from 140°F water in 6 seconds.
Annual testing of reduced-pressure and double-check backflow assemblies is required by the 2021 IRC (P2503.8.2).
Inverness, Florida's final checklist asks for a shutoff at each fixture except residential tubs and showers.
A water heater on a supply with a check valve, pressure-reducing valve or backflow preventer needs thermal expansion control under 2021 IPC 607.3.

Trim-out is the last plumbing stage of a remodel or new build, and it is the one you can see. Everything roughed in and tested at top-out now gets a fixture, a valve or a cover plate, and the building department comes back once more.

What is plumbing trim-out?

Plumbing trim-out (finish plumbing) is the stage where the plumber connects fixtures to the stub-outs left at rough-in, after drywall, tile and flooring are in. Toilets, lavatories, kitchen sinks, faucets, shower handles and spouts, stop valves and supply lines all go in now; each is then run and checked for drips. The 2021 IRC keeps fixtures out until the rough inspection has passed, so trim-out always comes after the walls close.

What gets installed at trim-out?

Fixtures, the valves that feed them and the visible trim are installed at this stage. Each sink and toilet gets an angle stop and a supply line, the shower valve body that was roughed in gets its cartridge, handle and escutcheon, and the toilet is set on its flange. Fixtures must match the rough-in: the Kohler K-3654 sheet, for example, needs at least 12 inches from wall to drain center, fixed back at toilet rough-in.

Trim-out: Stop valves, supply lines and the trim-out punch list

Outside video from the Amtrol Inc. YouTube channel: What Is A Thermal Expansion Tank? - Amtrol Tech Takes. Chosen for a point this page makes. It is shown so you can see what the work involves, not as a homeowner how-to; Trench to Trim has no arrangement with this maker, though the supply house run by its owners may sell the maker's products. Only the preview picture loads from YouTube until you press play.

Which safety devices go in at the finish?

Three groups of safety devices are set or checked at trim-out: scald limits, backflow protection and thermal expansion control. The shower valve's limit stop is adjusted once hot water is on; ASSE International says the installer must come back to set it if hot water is not yet available. Hose bibbs get vacuum breakers, irrigation lines get a backflow assembly, and the water heater gets an expansion tank where the code your city adopted calls for one.

Licensed work and safety stops at the finish

Gas connections to a water heater, range or dryer, and any water heater venting, belong to a licensed plumber or gas fitter and are inspected separately.
Smell gas? Get everyone out now; don't flip switches, use phones, light anything or start a car inside. Once outside and away, call 911 or the gas utility.
Backflow assemblies are installed by a licensed plumber and tested by a certified backflow tester.
The relief valve and its discharge pipe on the water heater stay in place and open-ended; a capped or cut-short pipe is a stop item.
Your building department and a licensed plumber have the final word.

What does the final inspection cover?

The final plumbing inspection confirms the finished system matches the permit: fixtures connected and working, the water heater installed to code, safety devices in place and no leaks. Under the 2021 IPC it happens once the building is complete and ready for occupancy. City checklists add local detail; West University Place, Texas looks at accessible sewer cleanouts, hose bibb backflow preventers and access panels for tubs and the main water valve.

What should you keep after the final?

Keep the signed-off permit card or final inspection record, the fixture and valve installation sheets, water heater manual and warranty, and any backflow test report. Moen prints "these instructions must be left with homeowner" on its Posi-Temp valve sheet, and ASSE International notes that seasonal swings in cold water temperature can call for resetting the limit stop. Add the photos of the open walls you took before drywall.

How does trim-out fit into a remodel schedule?

Trim-out comes after drywall, waterproofing, tile, paint and countertops, and before the final inspection and the last payment. New Jersey's construction code spells out that rough inspections come before insulation and interior finishes; trim follows those finishes as normal trade practice.

Trim-out numbers

120°FMaximum limit-stop setting for shower and tub-shower valves (2021 IPC 412.3)International Code Council
6 secondsExposure to 140°F water that gives most adults third-degree burnsCPSC
3Required plumbing inspections in the 2021 IPC: underground, rough-in, finalInternational Code Council
1 yearRetest interval for testable backflow assemblies (2021 IRC P2503.8.2)International Code Council
80 psiStatic pressure above which the 2021 IPC requires a pressure-reducing valveInternational Code Council

What happens at trim-out and who checks it (model codes and city checklists, read October 2026)
Item	What goes in	Who sets or checks it	Keep or photograph
Toilets and sinks	Fixture, angle stop, supply line, trap	Plumber; inspector at final	Model numbers and installation sheets
Shower and tub valves	Cartridge, trim, limit stop at 120°F maximum	Plumber sets the stop; inspector may check	Valve sheet with limit-stop steps
Hose bibbs and irrigation	Vacuum breaker; backflow assembly	Plumber; certified tester for assemblies	Backflow test report
Water heater	Shutoff, relief valve pipe, expansion control	Plumber; inspector at final	Manual, warranty, expansion tank label
Whole system	Leak check and final drainage test	Inspector	Final inspection record

Letterpress-style chart titled Trim-out to final, with five numbered steps: 1 finishes done, tile, paint and counters; 2 fixtures set, toilets, sinks, faucets and shower trims; 3 stops and supply lines connected; 4 leak check, limit stop set to 120°F maximum; 5 final inspection, permit closed. Source line: 2021 IPC 108.2 and 412.3; ASSE International.

Pressman's note

This page draws on the 2021 IPC and IRC (International Code Council), the 2024 UPC (IAPMO), ASSE International's white paper on limit stops, the CPSC scald publication, city checklists from Inverness, Florida and West University Place, Texas, and maker sheets from Kohler and Moen, all read in October 2026. Section numbers follow those editions; your city may use another edition with local amendments. Prices, brand rankings and installation steps are left out.

Questions from the job site

Is trim-out the same as finish plumbing?

Yes. Bids and schedules use trim-out, trim and finish plumbing for the same stage: connecting fixtures and visible valves to the piping roughed in earlier. Ask the plumber which fixtures and connections their trim line includes.

Can the painter or tile setter work after trim-out?

Usually they finish first, because fixtures and escutcheons sit on the finished surface. Tile, grout and countertops set after the faucets risk damage and gaps behind trim plates.

How long after trim-out is the final inspection?

It depends on how fast your building department schedules inspections and whether the other trades are ready. The 2021 IPC puts the final after the building is complete and ready for occupancy, so ask your general contractor how the plumbing final is timed against the electrical and mechanical finals.

Who sets the shower temperature limit?

The installer sets the limit stop by following the valve maker's instructions once hot water is available. If hot water was not on at trim, ASSE International says the installer should come back and set it, and the inspector should note it on the final report.

What if a fixture leaks after the final?

Call the plumber who did the work and check whether your contract includes a workmanship warranty. A drip at a compression nut or supply line is a quick fix for them, and catching it early protects the new floor and cabinet.

Does the limit stop ever need resetting after the final?

It can. ASSE International notes that seasonal swings in cold water temperature can call for resetting a shower valve's limit stop, so a valve that was right in summer may run hotter or cooler in winter. Keep the valve's instruction sheet, and ask the plumber to recheck the setting if the hottest shower water feels different from season to season.