Tile Calculator Guide

Ceramic vs Porcelain Tiles

Both calculate the same way (area ÷ tile size), but coverage differs slightly due to thickness and cutting.

Ceramic Tiles

• Lighter, easier to cut
• Less waste during cutting (cleaner breaks)
• Standard 10% wastage sufficient
• Wall tiles typically ceramic

Porcelain Tiles

• Harder, denser (more breakage during cutting)
• Add 12-15% wastage instead of 10%
• Best for floors, bathrooms, kitchens
• Large format (600×600mm, 800×800mm) popular

Grout Joint Width

Grout spacing affects how tiles fit. Wider joints mean fewer tiles needed, but the difference is small.

For calculation purposes, ignore grout width unless using 10mm+ joints (rare). The difference in tile count is under 2%.

Mosaic Tiles

Small tiles (typically 25×25mm to 50×50mm) come pre-mounted on 300×300mm mesh sheets.

Calculate by m² area, not individual tile count. One sheet = 0.09 m².

Example: 3 m² bathroom splashback ÷ 0.09 m² per sheet = 33.3 sheets. Buy 37 sheets (10% wastage + spares).

Mosaic Wastage

Mosaic waste is higher than standard tiles:

• 15% wastage minimum (cutting mesh is fiddly)
• Border tiles often need individual removal from mesh
• Pattern mosaics: 20% wastage if you're matching a design

Large Format Tiles

Tiles over 600mm are popular for modern minimal looks, but have drawbacks for calculation.

900×900mm and 1200×600mm Tiles

• Fewer tiles needed (obvious)
• Higher wastage: large tiles crack more easily during cutting
• Add 15-20% wastage
• Often sold individually or in small packs (2-3 tiles)

Small rooms with large tiles = lots of cuts. A 2.5m bathroom with 900mm tiles means every tile gets cut. Consider 600mm instead.

Natural Stone Tiles

Marble, slate, travertine, limestone calculate like porcelain but need extra consideration:

• Edges less precise than manufactured tiles
• Use 5mm grout joints minimum (hides variation)
• Wastage 15% (stone breaks unpredictably)
• Buy from same batch/pallet (natural variation between batches)

Calculating for Patterns

Brick Bond (Offset/Running Bond)

Each row offset by half a tile length. Standard 10% wastage applies. Popular for metro tiles and rectangular formats.

Herringbone

Tiles at 90-degree angles in zigzag pattern. Every edge tile needs a 45-degree cut. Add 20% wastage.

Checkerboard

Alternating colours in grid. Calculate total area then split by colour (e.g. 50/50 split for black and white). Each colour needs its own wastage allowance.

Tips

• Buy all tiles from same batch (batch number printed on box)
• Order at least one extra box for future repairs
• Unopened boxes often returnable within 30 days
• Tile depth matters for floors: thin tiles (6-8mm) for level matching, 10mm+ for durability
• Use our tile calculator for instant results