Roofing Materials Calculator

Calculate exactly how many roof tiles, metal sheets, timber battens, screws and underlay you need for any roof. Enter your roof area and material type for a complete material list instantly.

Quick answer: Concrete tiles: approximately 16 tiles/m². Metal sheets: depends on sheet width and cover. Battens: 1 row per 300–350mm of rafter. Always add 10% waste.

🔨 Roofing Materials Calculator

Use the Roof Area Calculator first to get true sloped area
Colorbond cover width: 762mm standard
Typical: 300–350mm for concrete tiles
Primary Material
Battens (lm)
Underlay (m²)

📐 How It Works

Roofing materials are calculated from the true sloped roof area. Tiles are counted by coverage rate per m². Metal sheets are calculated from cover width. Battens are spaced to suit the tile gauge and run horizontally across the rafters. Underlay goes under tiles and battens.

Tiles = Roof Area × Tiles/m² × (1 + Waste%) Sheets = Roof Area ÷ Cover Width × (1 + Waste%) Batten lm = Roof Area ÷ Batten Spacing

📋 Worked Example

A 130 m² roof in concrete tiles: Tiles = 130 × 1.10 × 16 = 2,288 tiles. Battens at 330mm: 130 ÷ 0.33 = 394 lm of batten. Underlay = 143 m².

❓ Frequently Asked Questions

Standard concrete roof tiles cover approximately 15–17 per m² depending on the tile profile and gauge. Terracotta tiles: 12–16/m². Always use the manufacturer's specified gauge for accurate counts — the gauge (vertical spacing) determines how many rows per metre of rafter.

Standard Colorbond roofing sheet cover width is 762mm (nominal). Allow for laps — end laps of 150mm minimum and side laps of one rib. For the true cover width of your specific profile, check the manufacturer's datasheet.

Batten spacing (gauge) is determined by the tile manufacturer's specification for the roof pitch. For most concrete tiles at pitches 15–35°: 300–340mm gauge. Never exceed the manufacturer's maximum gauge — this affects weatherproofing. Always check the tile specification sheet.

Yes — sarking or roofing underlay is required under most tile and sheet roofing in Australia per AS 4200. It provides a secondary weather barrier and improves thermal performance. Allow 10–15% extra for laps and waste.