Tile Adhesive & Grout Calculator

This calculator works out how much tile adhesive and grout you need for a tiling job in New Zealand, two materials that are easy to under-buy and frustrating to run out of mid-job. Tile adhesive, the cement-based mortar that bonds tiles to the wall or floor, is used at a rate that depends mostly on the trowel size and tile, typically around 3 to 5 kilograms per square metre for standard tiles with a notched trowel, more for large-format tiles that need a thicker bed. Grout, which fills the joints between tiles, depends on a different set of factors: the tile size, the tile thickness, and the joint width, because thin tiles with wide joints and small mosaics use far more grout per square metre than large tiles with hairline joints. Getting both right means you buy enough without overspending on bags that will harden in the garage. You enter the area to be tiled, the tile length and width, the tile thickness, the joint width, and the adhesive coverage rate, and the calculator returns the adhesive in kilograms and 20kg bags, and the grout in kilograms. This lets you order with confidence and check a tiler's materials list. For best results, match the adhesive type to the tile and substrate, especially for large tiles, wet areas and underfloor heating, and always follow the product's coverage figures, which this calculator lets you set. Buy a little extra of both, since coverage varies with substrate flatness and technique. Treat the result as a close estimate to plan your purchase.

Adhesive use depends on trowel and tile size; large-format tiles need more. Buy a little extra of both. An estimate; follow the product coverage.