Tile Grout and Adhesive Quantity Calculator
Calculate the quantity of grout and adhesive required for your tiling project based on the area to be tiled, tile dimensions, joint width, and tile thickness.
Formulas Used
Grout quantity (kg/m²):
Grout Volume (L/m²) = [(L + W) / (L × W)] × J × T
Grout Mass (kg/m²) = Grout Volume × Grout Bulk Density
Where:
L = Tile length (mm)
W = Tile width (mm)
J = Grout joint width (mm)
T = Tile thickness (mm)
The factor (L + W) / (L × W) represents the total joint perimeter length per unit area of tiled surface. Multiplying by joint width J and tile thickness T gives the joint volume. The unit algebra resolves to L/m² when all linear dimensions are in mm.
Adhesive quantity (kg/m²):
Adhesive Volume (L/m²) = Bed Thickness (mm) × Coverage Factor (0.70) Adhesive Mass (kg/m²) = Adhesive Volume × Adhesive Density Coverage Factor = 0.70 (standard notched-trowel application ≈ 70% solid contact)
Total quantities with wastage:
Total (kg) = Rate (kg/m²) × Area (m²) × (1 + Wastage% / 100)
Assumptions & References
- Grout formula follows the ANSI A108.10 standard and is widely cited by manufacturers (Mapei, Laticrete, BAL).
- A notched-trowel coverage factor of 70% is assumed for adhesive, consistent with BS EN 12004 and tile industry guidelines (TCNA Handbook).
- Grout bulk density default of 1.6 kg/L is typical for cement-based unsanded grout; sanded grout is typically 1.7–1.8 kg/L.
- Adhesive density default of 1.5 kg/L is typical for standard cementitious tile adhesive (C1/C2 class per EN 12004).
- A 10% wastage allowance is recommended as a minimum for straight-lay patterns; diagonal or complex patterns may require 15–20%.
- Adhesive bed thickness of 6 mm is a common minimum for wall tiles; floor tiles on uneven substrates may require 10–12 mm.
- Results are estimates. Always verify with your specific product data sheet (PDS) before purchasing.
- References: TCNA Handbook for Ceramic, Glass, and Stone Tile Installation; BS 5385; EN 12004; Mapei Grout Calculator methodology.