LayoutWise

Shower Tile Calculator

Enter the back wall, the side walls, how high you'll tile and the tile size. You see every tile and cut on all three walls, plus the niche, the floor and every material on one list.

Your shower

1. Shower alcove
Back wall width
ft
in
Side wall depth
ft
in
Tile height
ft
in
2. Wall tileGrout joint
3. Niche and floor

Wall tiles

66

12" x 24", +10%

Wall area

84.4 sq ft

niche included

Floor sheets

16

12" x 12" mosaic

Waterproof

108 sq ft

walls + floor

Tile layout, walls unfolded

cut tile
Left wall · 2' 8"Back wall · 5' 0"Right wall · 2' 8"

Full rows start at the bottom and the cut row lands at the top. Columns are centered on each wall so both corner cuts match. Snap a level line — shower pans slope, so don't trust the floor.

Shopping list

  • ✓Wall tile: 132 sq ft — 66 tiles (12" x 24" (laid horizontal), includes 10% extra)
  • ✓Shower floor: 16 mosaic sheets, 12" x 12" (2" x 2" tile slopes to the drain better than large tile)
  • ✓Thinset: 3 x 50 lb bags of polymer-modified mortar rated for large-format tile
  • ✓Trowel: 1/2" x 1/2" square-notch for the walls, 1/4" x 1/4" square-notch for the floor
  • ✓Grout: 1 x 25 lb bag (or 9 lb) — unsanded or epoxy grout for 1/8" and narrower joints
  • ✓Cement backer board: 7 sheets, 3' x 5' (skip if you use foam board)
  • ✓Waterproofing: 108 sq ft of membrane — about 3 gallons of liquid membrane at two coats
  • ✓Edge trim: 16 ft for the open edges, plus 6 ft for the niche
  • ✓100% silicone: 1 tube for the 16 ft of inside corners and the floor joint (do not grout changes of plane)

Shower pan, curb and drain are not included. Check that your membrane is rated ANSI A118.10 and follow its coverage and cure times.

Measure the shower

A standard alcove has a back wall the length of the tub or pan (usually 60") and two side walls (usually 30"–36" deep). Tile at least to the height of the shower head. Most people go to 84"–96", or all the way to the ceiling, which looks cleaner and avoids a trim line.

How the layout is planned

Columns are centered on each wall, choosing a grout joint or a tile on the center line — whichever leaves the wider cut pieces in the corners. Full rows start at the bottom and the cut row ends up at the top, where it's least visible. The planner warns you if a corner piece would be a thin sliver.

Shower niche

A niche between studs at 16" on center can be up to about 14½" wide without changing the framing. Set the bottom at a comfortable height — 42"–48" is common — and slope the bottom shelf slightly toward the shower so water drains out. The niche adds its back plus four 3½"-deep sides to the tile count, and needs edge trim or mitered tile on the front.

Shower floor

Small mosaic tile (2" x 2" or smaller) follows the slope to the drain and gives more grip because of the extra grout lines. The floor is figured in 12" x 12" sheets with 15% extra for cuts around the drain.

Waterproofing comes first

Tile and grout are not waterproof. Behind them you need either cement backer board covered with a liquid or sheet membrane, or a foam board system. Choose a membrane rated ANSI A118.10, and lap it onto the shower pan. The planner covers all wet walls and the floor, with 10% extra for overlaps.

Thinset, grout and corners

Use polymer-modified thinset on walls, and a mortar rated for large-format tile when any side is 15" or longer. Large tiles also need a deeper trowel and should be offset no more than a third of their length. Use unsanded or epoxy grout for joints of 1/8" or narrower. In the inside corners and where the walls meet the floor or tub, use 100% silicone instead of grout — those joints move, and grout there cracks.

Doing a kitchen wall too? Try the backsplash planner, or check the bags with the thinset and grout calculators.