---
title: "Check 8: 24-Hour Flood Test Protocol"
url: https://stacklist.com/card/ca20bcfe-2813-4711-a2e7-9c2740e56a9f
stack: https://stacklist.com/c/business/stack/8b50c285-c1e7-42de-ac4c-343659a54e54
summary: "Check 8: 24-Hour Flood Test Protocol is a mandatory quality assurance procedure for roofing membranes that requires water to be held at minimum 1 inch depth for 24 hours with acceptable water loss not exceeding 1/4 inch. The test must be completed and documented before drainage mat installation and is required for FM warranty submittal."
tags: "flood-test, roofing, quality-control, membrane, checklist, waterproofing, inspection"
key_entities: "24-Hour Flood Test (concept), FM warranty (concept), membrane cure verification (concept), drainage mat (concept), evaporation allowance (concept)"
classification: "checklist"
content_hash: "sha256:f65dbffaabe83de5fb6dc0caf758d995799ef6601b0e7a7bdc97dc8191c59c7c"
acp_version: "0.2"
token_counts_approximate: 666
visibility: public
agent_accessible: true
status: "final"
---

# Check 8: 24-Hour Flood Test Protocol

Check 8: 24-Hour Flood Test Protocol 
Mandatory Hold: Flood test must be completed and documented before drainage mat is installed. A
passing result is required for FM warranty submittal. 
When to Flood Test 
Flood test is performed AFTER membrane cure verification (Check 6) passes 
Flood test is performed BEFORE drainage mat is placed 
All penetrations, transitions, scupper details, and wall terminations must be complete before
flooding (Checks 3, 4, 5) 
Setup 
[ ] All drains are temporarily plugged with inflatable or mechanical plugs rated for standing water 
[ ] All scuppers are temporarily plugged or dammed 
[ ] Plug type and installation method documented: no plugs that could damage the membrane 
[ ] Area below and adjacent to the deck is inspected and cleared before fill begins 
[ ] Weather forecast confirms no rain or freezing temps during the 24-hour hold 
Fill 
[ ] Water is introduced slowly: no high-pressure fill that could dislodge plugs or damage membrane 
[ ] Water depth reaches a minimum of 1 in. over the entire test area 
[ ] Water depth is uniform: no areas with less than 1 in. coverage 
[ ] Fill depth is measured and recorded at the start of the test 
[ ] Start time is recorded 
Hold Period 
[ ] Minimum 24-hour hold: no draining before the full period elapses 
[ ] Water level is checked at 12 hours: any significant drop triggers immediate investigation 
[ ] No traffic on the flooded deck during the hold period 
[ ] Water level at 24 hours is measured and recorded 
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Pass/Fail Criteria 
Pass: Water level at 24 hours is within 1/4 in. of starting level (allowance for evaporation) 
Fail: Water level drop exceeds 1/4 in., or visible leaks are observed at any point 
On Failure 
1. Drain the deck immediately 
2. Locate the leak: start at all laps, penetrations, and scupper edges 
3. Repair per FM detail and allow to cure 
4. Re-run the full 24-hour flood test before proceeding 
Flood Test Log 
Item Value Inspector Date/Time 
All plugs installed [ ] __________ __________ 
Fill start time __________ __________ __________ 
Starting water depth ________ in. __________ __________ 
12-hour check: water level ________ in. __________ __________ 
24-hour check: water level ________ in. __________ __________ 
Water loss (evap allowance) ________ in. __________ __________ 
Pass / Fail __________ __________ __________ 
Photos attached [ ] __________ __________ 
Do not proceed to drainage mat until flood test log is signed and photos are attached. 
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