Plumbing As-Built Documentation: What to Capture and When (2026)

John Dutton

Plumbing as-built documentation is the record of where your pipes, valves, and fixtures actually ended up — not where the drawings said they'd go.

For plumbing contractors, this matters more than in almost any other trade. Pipes are hidden inside walls and floors. They can't be inspected after installation without damage. The only record is what you captured before the walls closed.

What plumbing as-builts need to include

Supply system

Main water entry point and meter location
Main shut-off valve location — GPS-tagged, with photo
All branch shut-offs — every zone, every fixture isolation valve
Complete supply run documentation before walls close
Pipe material, sizing, and any transitions between materials

Drain, waste, and vent

All clean-out locations — GPS-tagged and measured from fixed reference points
DWV stack locations
Roof penetration locations
Under-slab drain runs if applicable — critical to capture before pour

Fixtures

Final installed locations for all fixtures
Rough-in dimensions as installed (vs as specified)
Any deviations from the original plan, with reason noted

Mechanical rooms and utility spaces

Water heater location, model, serial number
Pressure reducing valve location and setting
Backflow preventer location and test record

The under-slab problem

Under-slab plumbing is the highest-stakes documentation in residential and commercial work. Once the concrete is poured, pipe locations exist only in records. The contractor who photographed every run with GPS tags before the pour can pull up exact locations years later. The contractor who didn't photograph anything is guessing — and billing for exploratory work that a client won't want to pay for.

Manifold's Orbit Measure scans capture the full geometry of a mechanical space from any phone. Walk a crawl space or utility room before it's closed in. The 3D model is measurable forever — future plumbers can take dimensions remotely without a site visit. See our rough-in documentation guide and the full as-built records workflow.

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