Project estimating guide
Tile Waste and Box Rounding: Order the Right Quantity
Tile ordering has two separate adjustments: a chosen allowance for cuts and a retailer’s complete-box increment. Keep both visible so you know why purchased coverage exceeds the measured surface.
Reviewed September 6, 2026Calculate measured and adjusted areas
For a 180 ft² surface, a 10% allowance produces 198 ft² to plan for. If each tile actually covers 1 ft², that corresponds to 198 pieces. At eight pieces per box, the purchase is 25 boxes or 200 tiles.
Compare allowance scenarios before ordering
An allowance should reflect the layout, cuts, and spare material you actually want. The table is a sensitivity comparison, not a universal prescription.
180 ft² with 1 ft² tiles, 8 per box
| Allowance | Tiles before box rounding | Whole boxes | Purchased tiles |
|---|---|---|---|
| 5% | 189 | 24 | 192 |
| 10% | 198 | 25 | 200 |
| 15% | 207 | 26 | 208 |
Check the layout and product
Narrow perimeter cuts, borders, diagonal layouts, and mosaics can behave differently. The tile calculator uses face area and does not claim to optimize the layout or grout gaps. Check the actual product dimensions and plan before committing to the order; keep adhesive, grout, waterproofing, and trim as separate quantities.
Sources and product references
- Pergo — installation guides
Use installation instructions for the particular flooring product.
- NIST — SI units: volume
Unit relationships; supplier product coverage and prices remain separate inputs.