Measure the main walls
For each wall, multiply tiled width by tiled height and identify large untiled openings.
Keep walls separate when tile direction, pattern, or product changes.
Unfold niches and benches
A niche adds its back plus four returns; a bench adds top, face, and side planes receiving tile.
Small planes often consume more cut pieces per square foot.
Measure shower floor independently
The pan can use a different mosaic or smaller format than walls.
Slope and drain cuts affect layout even when plan area is unchanged.
Round by SKU and carton
Apply cut allowance to each tile product, divide by exact carton coverage, and round up.
Keep trim profiles and specialty pieces separate.
Do not infer waterproofing from tile quantity
Tile and grout are finish materials; waterproofing and drainage are separate system requirements.
Follow shower-system and tile-manufacturer instructions.