Mapei Grout Calculator

How the Mapei Grout Calculator works

Formula. Tile area in square feet is (width in inches / 12) × (length in inches / 12). Tiles needed = area / tile area. Grout length in feet = tiles × 2 × (width + length) / 12. Cubic feet = (grout length × joint width × joint width) / 144. Pounds = cubic feet × 13.4.

Example. 100 square feet of 12 by 12 inch tile with a 0.125 inch joint needs 0.043 cubic feet of grout, which is 0.043 × 13.4 = 0.58 pounds.

Limitation. The 13.4 pounds-per-cubic-foot factor and the joint-width-squared volume are estimates in the script, not a specific Mapei product yield chart.