Layout, Grouting, and Finishing
Layout, Grouting, and Finishing
This domain tests layout geometry, cut planning, grout selection and installation, and final finishes. Exam items may ask you to choose a starting line, compute a cut, select grout, or identify where sealant replaces grout.
Core rules
- Establish square reference lines using the 3-4-5 method or a laser; check room squareness before snapping layout lines. A story pole marks course heights and avoids cumulative error.
- Center the layout on prominent sightlines and avoid cuts narrower than half a tile where possible. Balance cuts at both ends; full tiles at an outside corner may be preferable to a sliver.
- Grout joint width must suit the tile and intended look; keep it consistent. Cementitious grout is mixed to a stiff consistency, packed diagonally, struck, and cleaned before haze sets. Epoxy grout needs strict proportioning and short working time.
- Movement joints at perimeters, changes of plane, and large fields take flexible sealant, not cement grout. Caulk changes of plane and fixtures.
- Final finishing includes removing haze, polishing, installing trim, and protecting the floor from traffic until cure.
Worked example
A wall is 122 in. wide and receives 12-in. tile with 1/8-in. joints. Ten tiles plus nine joints equal 121.25 in., leaving only 0.75 in. total-3/8-in. slivers at each end. Use nine full tiles plus eight joints (109 in.), leaving 13 in.; center that, and each end cut is 6.5 in., a stable, visible cut.
Traps
Starting with a full tile at a prominent door and leaving a sliver at the opposite wall; using cement grout in movement joints; washing grout with too much water; and failing to check diagonal squareness before setting.