How to measure a shower for tile square footage
Shower tile square footage is the combined area of every surface you're covering — the three enclosing walls and the floor pan, measured in square feet. Because tile is priced by the square foot and sold by the box, an accurate figure tells you exactly how many boxes to buy and keeps you from a second trip when the dye lot has changed. The math is straightforward: width times height for each wall, plus length times width for the floor.
Start with the three walls. Measure the width of each and the height you intend to tile — most walk-in showers run tile all the way to the ceiling, often around 8 feet. Multiply width by height for each wall and add them together. Then measure the pan as a simple rectangle and add it in. The calculator above handles the multiplication and the waste factor; you just enter each surface. If you're tiling only part of the wall height, treat it exactly like any other wall area — width times the tiled height.
Why a shower needs a waste factor
You can't tile a shower without cutting tile. The valve, the shower head, the drain, the niche, and every inside corner force cuts, and cut offcuts usually can't be reused. Because of that, tile setters order about 10% more than the measured area for a straight-laid shower, and closer to 15% for diagonal patterns or large-format tile where breakage and trimming waste more material.
A recessed niche adds a little area of its own — the back panel plus the sides and shelf — so add a couple of square feet per niche rather than ignoring it. Once you have the total, you can drop it into the square footage cost calculator with your price per square foot to turn the measurement into a materials budget.
Do you tile the shower floor, and what about the door?
Yes — the floor or pan is a tiled surface and belongs in your total. It's usually small-format mosaic for grip and to follow the slope to the drain, so order it as a separate product from the wall tile. Measure it as a plain length-by-width rectangle and add it to the wall figure before applying waste.
The door is the one surface you may leave out. A frameless or framed glass enclosure isn't tiled, so subtract that opening from the wall you'd otherwise cover. A tub-shower with a curtain has no glass, so you tile the full run of each wall with nothing to subtract.