Tile Calculator — NZ

Divide 1 m² by (tile length × tile width), including the grout joint. For 300×300 mm tiles with a 3 mm joint: 1 ÷ (0.303 × 0.303) ≈ 10.9 tiles/m². Always add 10% for cuts, 15% for diagonal laying.

Standard notched trowel application uses approximately 3–4 kg of adhesive per m². Large-format tiles (600+ mm) using the back-butter method may use 5–6 kg/m². A 20 kg bag covers about 4–6 m².

Professional tiling in NZ costs $60–$100/m² for labour only (floor tiles, straightforward room). Bathroom wall tiling or complex floor patterns (herringbone, diagonal) costs $80–$130/m² labour. Tile supply is additional.

NZ tile industry guidance: 2–3 mm for rectified tiles (machine-cut), 3–5 mm for standard tiles, 8–10 mm for irregular or natural stone. Wider joints accommodate variation in tile size and are easier to keep clean.