Before shower tile goes up, ask the installer to identify the waterproofing system and show you its written test instructions. The water test, when required or recommended for that system, needs to happen while the membrane, seams, drain connection, and shower base are still visible. Once tile is installed, those details are covered.
There is no one timing rule for every system
Water-test procedures depend on the waterproofing product and the shower assembly. For example, Schluter's instructions for its KERDI shower system describe a water test before setting tile. Schluter says to wait at least 24 hours after setting KERDI before starting that test, and describes 24 hours as typical for the test itself. Those timings apply to that system's guidance. They are not a universal schedule for every membrane or a substitute for local inspection requirements.
Ask which product is specified and check its current installation instructions. Also confirm with the local building department whether the project needs a plumbing or waterproofing inspection before the tile work proceeds. Requirements can depend on the jurisdiction and approved scope.
What to confirm before the work is covered
Ask the remodeler to put the system name in the scope and explain which surfaces it covers. Have them point out how the floor, corners, curb or entry, niche, plumbing openings, and drain are handled under that system. The products and details vary, so the product instructions should govern the actual assembly.
Then agree on the checkpoint: who performs the test, when it can begin under the manufacturer's instructions, how long the water remains in place, how the level or result is recorded, and who confirms that tile can proceed. If the city or other authority has an inspection step, coordinate it before scheduling the tile setter. Keep dated photos of the exposed installation and the test result with the project records.
Questions to ask your shower installer
- What waterproofing product and installation method are in the written scope?
- Where can I read the manufacturer's current water-test instructions?
- Does this job require a local inspection before tile, and who schedules it?
- What will be documented before the membrane is covered?
- Who confirms the test or inspection is complete before tile starts?
A clear answer ties the product, test, inspection, and tile schedule together. Quest's full-remodel service covers bathrooms and interior work. For another finish-sequencing question, see our guide on whether new flooring should go under kitchen cabinets.
Before tile hides the shower assembly, identify the system, follow its test instructions, and confirm any required inspection.
