How to Calculate Tile Needed for a Shower

Calculating the tile needed for a shower is essential for budgeting, ordering, and avoiding delays during a bathroom remodel. This guide explains step-by-step measurements, waste allowances, tile counts for different sizes and layouts, and practical examples to ensure an accurate estimate. Accurate measurements and a realistic waste factor are the two most important elements for a successful tile order.

Area To Tile	Typical Waste Allowance	Quick Estimate Tip
Shower Floor	10–15%	Use smaller tile = more grout, larger tile = fewer cuts
Shower Walls	10–20%	Include niches, benches, and threshold tiles
Mosaic Or Small Tile	15–25%	Buy extra sheets for pattern matching

Measuring The Shower Area

Start with accurate measurements of every surface to be tiled: shower floor, each wall from floor to ceiling or to the top of the surround, shower curb, bench, and niches. Precision in measuring square footage is the foundation for the entire calculation process.

Measure the width and height of each wall in feet and inches. Multiply width by height to get square feet for each wall. For the floor, measure length and width of the base or use triangulation for irregular shapes. Record each measurement separately.

Common Measurement Considerations

Account for features that reduce tile area such as doors or windows, and features that increase it like built-in benches and niches. Always measure these elements individually so they can be added or subtracted accurately from the total square footage.

Accounting For Wastage And Cuts

Tiling a shower always generates waste from cut tiles, pattern matching, and breakage. Standard waste allowances vary by project complexity and tile size. Set a realistic waste percentage before ordering to prevent shortages.

Recommended waste factors: 10% for straightforward installations with large tiles, 15% for typical projects, and 20–25% for small tiles, mosaics, or diagonal layouts. For niches or intricate patterns, plan toward the higher end of the range.

Selecting Tile Size And Layout

Tile size and layout strongly affect how many whole tiles will be used and how much cutting is required. Larger tiles cover more area but may produce awkward cuts near corners; mosaics cover easily shaped areas but add grout. Choose tile and layout with both aesthetics and waste in mind.

Layouts include stacked, brick (staggered), subway, and diagonal. Diagonal or herringbone patterns typically increase waste by 5–10% due to irregular cuts. Also consider grout line width and tile trim pieces which can affect final materials needed.

Calculating Number Of Tiles

Convert total square footage for each surface into the number of tiles by dividing area by the tile’s coverage. Coverage is tile area (in square inches) converted to square feet, or refer to manufacturer’s square feet per box. Always calculate per surface then add totals for final quantity.

Example calculation: a wall 5 ft wide x 8 ft high = 40 sq ft. With 12×24 inch tiles (2 sq ft per tile), 40 ÷ 2 = 20 tiles. Add waste: 20 x 1.15 = 23 tiles, round up to 23 or 24 depending on box quantities.

Using Tile Boxes And Sheets

Tiles are typically sold by the box, with the box indicating square feet covered. For mosaics, sheets cover a certain square footage. Convert your total square footage to boxes using the manufacturer’s coverage and always round up to whole boxes.

Additional Materials To Budget

Tiling requires more than just tiles: thin-set mortar, grout, backer board, waterproofing membrane, sealant, and potentially specialty trim. Include these materials in cost and quantity estimates to avoid under-budgeting.

Thin-set coverage varies by trowel size; a 50 lb bag typically covers 50–80 sq ft. Grout quantities depend on tile size and joint width; use grout calculators or manufacturer tables. Add 5–10% cushion to adhesives and grout for real-world conditions.

Common Tile Patterns And Effects On Waste

Different patterns influence the number of cuts and offcuts. Staggered or running bond patterns can lead to more partial tiles at ends of rows, while mosaic sheets reduce cutting but require more grout. Select a pattern early to refine the waste percentage.

Diagonal patterns increase waste by about 10% because cuts at edges are often triangular. Herringbone and basketweave patterns require careful planning and typical waste of 15–20% for correct alignment and trimming.

Practical Example Calculations

This section walks through two detailed examples: a standard alcove shower and a curbless, tiled floor shower. Worked examples help translate abstract percentages into exact orders.

Example 1: Standard Alcove Shower

Assume three walls 5 ft wide x 8 ft high each and a shower base 5 ft x 3 ft. Walls: 3 x (5 x 8) = 120 sq ft. Floor: 5 x 3 = 15 sq ft. Total = 135 sq ft. Choose 12×24 tiles (2 sq ft each) for walls and 6×6 tiles (0.25 sq ft each) for floor.

Walls: 135 sq ft walls portion? If walls total 120, walls tiles = 120 ÷ 2 = 60 tiles. Add 15% waste = 69 tiles. Boxes: if boxes contain 10 tiles (20 sq ft), buy 7 boxes = 140 sq ft coverage. Floor: 15 ÷ 0.25 = 60 floor tiles. Add 15% waste = 69 tiles. If sold by box of 20 tiles, buy 4 boxes = 80 tiles.

Example 2: Curbless Tiled Shower With Mosaic Floor

Assume four walls (one open) totaling 96 sq ft and a curbless floor 4 ft x 6 ft = 24 sq ft. Choose large format 24×48 for walls, mosaic 1×1 sheets (1 sq ft per sheet) for floor.

Walls: 96 ÷ 8 (24×48 = 8 sq ft) = 12 slabs. Add 15% waste = 14 slabs, round up to 14. Floor: 24 sq ft of mosaics, at 15% waste = 27 sheets. Order extra sheets for pattern matching and future repairs, recommend buying 10% over the calculated waste again for supply stock.

Tips For Buying And Ordering

Always order extra tiles from the same production lot to avoid shade variation. Production lots can vary; buy all tiles at once or secure the lot number from the seller for future matching.

When ordering online or from a big-box store, request boxes to be opened to verify shade and finish if possible. For large projects, ask suppliers about delivery lead times, special order tiles, and return policies for unopened boxes.

Practical Tools And Calculators

Several reputable online calculators help estimate tile counts, grout, and thin-set needs using inputs for tile size, layout, and waste. Use manufacturer calculators and cross-check with manual calculations to catch errors and account for site-specific features.

Desktop spreadsheet templates work well for projects with many surfaces. Create columns for surface name, dimensions, area, tile coverage, tiles required, waste factor, and boxes to order. Sum totals for a consolidated shopping list.

Common Mistakes To Avoid

Typical errors include underestimating waste, failing to include niches and benches, ignoring tile lot numbers, and forgetting trim pieces. Double-check each measured surface and add a conservative waste margin to avoid mid-project shortages.

Avoid buying the minimum tiles; a shortfall can delay the job and create mismatched tiles from subsequent production runs. For custom or cement-based tiles, a larger buffer is prudent because remakes are not always identical.

Practical On-Site Considerations

Field conditions—uneven walls, out-of-square corners, and substrate imperfections—affect tile layout and cuts. Plan for on-site adjustments by allocating time and materials for test layouts.

Dry-lay tiles to visualize cuts and transitions before installing adhesives. This step helps identify problematic areas and refines the final tile count, potentially changing the waste percentage or showing where bullnose and trim pieces are needed.

Final Checklist Before Ordering

Before placing the final order, verify measurements, confirm tile quantities including waste, note the tile lot number and finish, and confirm lead times and return policies with the supplier. A verified checklist prevents costly mistakes and project delays.

1. Confirm All Surface Measurements And Calculate Total Square Footage
2. Decide Tile Size, Pattern, And Layout; Adjust Waste Factor
3. Convert Square Footage To Tiles And Boxes; Round Up
4. Include Thin-Set, Grout, Waterproofing, And Trim In Order
5. Check Lot Numbers, Order Extra For Repairs, And Confirm Delivery

Following these steps and using the worked examples will provide a reliable tile quantity estimate for most shower projects. Accurate measurement, realistic waste allowance, and awareness of tile-specific factors ensure materials are sufficient and the installation proceeds smoothly.