Layout model and usable dimensions
A tile purchase estimate does not reveal whether a room ends with a narrow strip along one wall. This straight-grid layout calculator starts with the usable rectangle after perimeter gaps, fits full interior tiles and grout joints, and shares the remaining width equally between the two border tiles. It performs the calculation in both directions and reports the border cuts and grid positions. Border tiles count as separate source pieces, with no assumed reuse of offcuts. Review cut sizes before ordering because centering on a room, doorway, or fixture can call for a different grid alignment.
Read the straight tile layout outputs
- Source tiles including spares
- Source tiles are a conservative cutting quantity, not the installed tile count.
- Grid rows
- Grid rows describe the fitted arrangement.
- Centered end cut length
- Centered end cuts refer to the usable field after specified clearances.
- Centered side cut width
- Side cuts must fit the source tile; a layout drawing is still needed around obstacles.
Fit, direction and offcut constraints
- The layout is a centered straight grid, not a diagonal, herringbone, or running-bond optimization.
- The reported source count is conservative for border cuts because cut-off sharing is not assumed.
- Very small border cuts can be avoided by changing grid alignment; dry-lay a sample row before installation.
Layout arithmetic and example
A worked example
A 10 × 8 ft floor with 1/4-inch perimeter gaps leaves 119.5 × 95.5 inches. With 12-inch tiles and 1/8-inch joints, the centered grid is 10 columns by 8 rows; five spares bring the source-tile budget to 85.
Avoid an impossible centered border
Suppose the usable field is 24.2 inches wide, each tile is 12 inches, and the joint is 0.125 inch. Two tile positions span only 24.125 inches. They cannot cover the field, even though the shortfall is just 0.075 inch. A three-position centered axis has one full center tile, two joints and two 5.975-inch border pieces.
A calculated border must fit inside the source tile. Check the full row and its joints before rounding a tile count.
Measure and compare a layout
- Measure the usable floor rectangle and set the installation-specified perimeter gap.
- Enter actual tile sizes and joint width, keeping length and width orientation consistent.
- Inspect centered border cuts and compare them with doorway or focal-point alignment.
Frequently asked questions
How can I avoid a small sliver tile at the wall?
Compare centered border cuts with a shifted grid. This tool gives a centered option so the two opposing borders share the leftover width.
Does this reuse tile offcuts?
No. Each grid position uses one source tile, which keeps the estimate conservative but may overstate material if paired cuts can share a tile.
Is the perimeter gap filled with grout?
Follow the installation system requirements for movement joints. A perimeter movement gap is distinct from the grout joint between tiles.
Read the project guides
- Tile Layout, Border Cuts, and Waste: Why Area Alone Is Not Enough
Compare tile-and-joint area estimates with centered grid positions, border cuts, source tiles, offcut reuse, and box rounding.
Calculation method: JICWH methodology. Examples are planning assumptions, not product recommendations.