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Trade walkthroughs

How to inspect tile work

Tile is unforgiving: a substrate that moves, a waterproofing lap that was skipped, or a thin-set coverage that was rushed becomes a cracked joint or a leak long after the crew is gone. This walkthrough follows the assembly from the substrate up, spending most of its attention on what happens before the tile is set, because that is where the failures are born.

For the tile foreman and the GC's superintendent verifying substrate, waterproofing and setting before the tile goes down, and the finished work before acceptance.

Step by step

  1. Verify the substrate is right for tile

    Confirm the substrate is the correct type, flat within the tolerance large-format or thin tile needs, sound, and free of movement and deflection. Tile is only as stable as what it is bonded to.

  2. Check waterproofing and any crack isolation

    In wet areas, confirm the waterproofing membrane is continuous, lapped and turned up correctly, with the flood test done and recorded where required. Where crack-isolation membrane is specified, verify it is in before any tile is set.

  3. Confirm layout, movement joints and mock-up

    Verify the layout against the plan and the approved mock-up — grout joint width, pattern, and where cuts fall. Confirm movement joints are planned at the perimeter and the intervals the assembly needs, not tiled over.

  4. Inspect the setting bed and coverage

    Check the mortar is the specified type, combed in one direction, with the coverage the assembly requires — pull a tile in an inconspicuous spot if coverage is in doubt. Hollow-sounding tile means the bed did not transfer.

  5. Verify lippage, alignment and joints

    Look down the plane of the tile for lippage within tolerance, consistent joint width, and true lines. Large-format tile shows every bit of lippage, so check it against the acceptance tolerance, not by feel.

  6. Check grout, sealant and the finished surface

    Grout should be full, uniform and cured, with sealant — not grout — in the movement and change-of-plane joints. The finished surface should be clean, free of haze, with no cracked, chipped or drummy tile.

What gets missed

  • Setting tile over a substrate that is out of flat beyond what large-format tile can hide.
  • Waterproofing skipped, un-lapped, or never flood-tested in a wet area before tile went down.
  • Movement joints tiled over with hard grout, so the assembly cracks when it moves.
  • Partial thin-set coverage that sounds hollow and lets the tile crack or debond.
  • Lippage judged by feel instead of against the acceptance tolerance for the tile size.

Questions people ask

Why is so much of a tile inspection before the tile goes on?
Because the failures that matter — movement, a leak, a debonded tile — start in the substrate, the waterproofing and the setting bed, none of which can be inspected once the tile is set and grouted.
How is thin-set coverage verified?
By pulling a set tile in an inconspicuous area to see the actual mortar transfer against the coverage the assembly requires, and by sounding the field for the hollow spots that mean the bed did not make full contact.

Terms worth knowing

Checklists that make this a one-tap job

Free, field-ready checklists, each with the photo every item needs before it can be submitted.

Tile and stone Rough-in· Tile and stoneTile and stone rough-in inspection checklistSubstrate, setting-bed system and dry layout confirmed before the first tile is set4 items7 photosTile and stone Pre-cover· Tile and stoneTile and stone pre-cover inspection checklistWaterproofing continuity, slope to drain and the flood test observed before tile hides them4 items9 photosTile and stone Final· Tile and stoneTile and stone final inspection checklistFinished tile checked for lippage, joints, honored movement joints and hollow-sound spots6 items10 photosTile and stone Punch· Tile and stoneTile and stone punch checklistCloseout walk for cracked or loose tiles, grout haze and sealant at plane changes4 items5 photos
See the whole checklist library

Related guides

Reading the steps is one thing. Proving you walked them is the job.

RTI holds the submit button until every mandatory item is answered and the photos are attached, then chains the record so it can be proven untouched later.

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