What is plumbing rough-inin construction?

All piping installed before surfaces close: underground DWV beneath the slab, in-wall and overhead waste, vent, and water distribution, stub-outs and test caps at every fixture location, fixture carriers for wall-hung units, and in-wall valves. It excludes the fixtures themselves, faucets, and final connections, which belong to the trim-out phase. The dividing line is simple: rough-in is everything that would be painful to reach after drywall, trim is everything you can still touch.

Top-out is the second half of rough-in. The underground (or first) rough places the below-slab DWV before concrete pours; top-out is the above ground rough that fills the framed walls and ceilings with supply, waste, and vent piping up through the roof penetrations. Each pass carries its own inspection and pressure test before cover. Some regions use the terms loosely, but on most US commercial jobs the inspection card lists underground, top-out, and final as separate sign-offs.

Good enough for budgets when the job looks like the history behind the number: grouped restroom cores, normal ceiling heights, conventional materials. The shorthand drifts when fixtures scatter, when wall-hung fixtures add carriers, when the structure forces core drilling, or when the DWV runs cast iron instead of PVC for acoustic reasons. Treat the per-fixture rate as a sanity check on a detailed lf-based takeoff for hard bids, not a substitute, and track your own history by building type.