Rough-in vs. trim-out as two distinct construction phases, water and DWV pressure testing requirements, multi-trade coordination sequencing, and the specific field installation errors that account for most real plumbing callbacks.
Rough-in installs every pipe, slope, and stub-out that has to be in place before walls close, weeks or months before trim-out sets a single fixture — and testing every rough-in system before it disappears behind drywall is what keeps an error from becoming a demolition problem later. This module works through DWV slope and hanger-spacing rules, worked hydrostatic and DWV pressure-test examples, and the multi-trade sequencing that determines when a wall is actually allowed to close.
By the end of this module you should be able to name the specific, recurring field errors — reversed slope, missing cleanouts, wet-venting sequence mistakes, under-spaced hangers, skipped pressure tests — that account for most real plumbing callbacks, and explain why each one is preventable with the discipline this module lays out rather than caught only after occupancy.