Free tile calculator. Tiles, adhesive and grout for a floor or wall at your tile size and joint width, with 10% wastage, or 15% for a diagonal layout.
This calculator counts tiles, adhesive and grout for a floor or wall, at the tile size and joint width you are using. Both the tile count and the grout come off the geometry of the joints, not off a flat rate.
A tile occupies its own size plus the joint beside it, so the area one tile covers is its width plus the gap, times its height plus the gap. Tile count is the area divided by that, rounded up.
Wastage is CostMate's allowance of 10%, or 15% if you switch on the diagonal or complex layout option, because a diagonal set-out cuts every perimeter tile.
A joint width of zero is taken as zero, so a butt-jointed floor is sized on the tile alone rather than on a default gap.
Sizes offered are 300 by 300, 400 by 400, 600 by 600 and 300 by 600mm, plus a custom size.
The grout figure moves a long way with the joint: a 10mm joint on 300 by 300 tiles takes over three times the grout of a 3mm one, so a flat rate per square metre cannot answer it.
Grout is worked out from the geometry of the joints themselves: the length of joint around a tile of a given size, at your joint width and your tile thickness. That is why the tile thickness field is there: a deeper tile means a deeper joint, and more grout sitting in it.
Adhesive is the maker's figure for ARDEX X 56, a standard cement-based tile adhesive: 6 square metres per 15kg bag on floors (2.5kg per square metre) and 8 on walls (about 1.9kg), from ARDEX NZ's product page. Pick floor or wall under the settings. ARDEX's technical data sheet quotes more coverage with a 10mm floor or 6mm wall notch; this page uses the product-page figures so you are not a bag short.
Waterproofing, substrate preparation and movement joints are specification decisions. Check them against your plans and the tile and adhesive manufacturers' systems, and confirm coverage figures on the product, before you order.