Quality Control
Plumbing Pressure Test — DWV & Supply
Perform code-required pressure tests before drywall closes the walls.
8 min James O'Brien Reviewed by Maria Delgado, Technical Reviewer, PE v1.1 · reviewed 2026-04-18
The Problem
Leaks discovered after drywall are 10x more expensive to repair. Missed pressure tests are a top cause.
Root Causes
- Schedule pressure to skip the test step
- Test held for insufficient time
- No documented test record
Correct Procedure
- 1Air- or water-test the DWV system per local code (typically 5 psi / 15 min)
- 2Water-test supply per code (typically 100 psi / 15 min after 24h stabilization)
- 3Foreman photographs the gauge at start and end
- 4File the test record with the inspector before requesting closure
Discussion Questions
Use these to engage the crew and connect the lesson to today's site conditions.
- 1What pressure and duration does our code require?
- 2How do we document the test for the inspector?
Sources & Review
Author: James O'Brien (25+ yrs) · Reviewed by Maria Delgado, Technical Reviewer, PE.
Published 2024-01-12 · Last technical review 2026-04-18 · Version 1.1 · Languages: EN, ES
AI at QST only summarizes expert-approved content and never invents safety requirements.
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