How Much Grout Do I Need?
Quick Answer
0.3–0.8 kg/m² for standard wall tiles, more for floor tiles
Based on: 300 × 600mm wall tiles with 2mm grout joints. Wider joints and thicker tiles need more grout.
How We Calculated This
Grout volume depends on tile size, tile thickness, and joint width. The formula uses the total length of grout joints per square metre:
- Tile size: 300 × 600mm, thickness 8mm
- Joint width: 2mm
- Joint volume per m²: ~0.0002m³/m²
- Grout density: ~1.6 kg/litre
- Grout per m²: ~0.3 kg/m²
- Example: 20m² bathroom = ~6kg = ~2.5 bags (2.5kg)
Grout Usage by Tile Size
- Mosaic (50 × 50mm, 2mm joint): ~1.5 kg/m²
- Metro (100 × 200mm, 2mm joint): ~0.7 kg/m²
- Standard wall (300 × 600mm, 2mm joint): ~0.3 kg/m²
- Floor tile (300 × 300mm, 3mm joint): ~0.6 kg/m²
- Large format (600 × 600mm, 2mm joint): ~0.2 kg/m²
- Natural stone (varied, 5mm joint): ~1.0–1.5 kg/m²
Types of Grout
- Cement-based (unsanded): For joints up to 3mm, walls. Most common.
- Cement-based (sanded): For joints 3–15mm, floors and wider joints.
- Epoxy grout: Waterproof, stain-resistant, ideal for wet rooms and kitchens.
- Flexible grout: For areas subject to slight movement (underfloor heating).
Tips
Mix grout to a thick, lump-free paste and let it slake (rest) for 5 minutes before use. Work in small sections (2–3m²) and clean off excess with a damp sponge before it sets hard. Use a grout float held at 45° to press grout firmly into joints. Seal cement-based grout with a grout sealer for long-lasting stain resistance.