---
title: "Roof Calculator — Roofing Squares, m², Shingles & Pitch Factor"
description: "Calculate roof area in roofing squares (US/CA) or square metres (UK/AU). Enter footprint and pitch to get true sloped area, material quantities, and waste allowance."
url: "https://worldcalculators.org/calculators/roof/"
canonical: "https://worldcalculators.org/calculators/roof/"
---

# Roof Calculator

Calculate roof area in roofing squares (US/CA) or square metres (UK/AU). Enter footprint and pitch to get true sloped area, material quantities, and waste allowance.

## Quick answer

A roofing square is 100 square feet (9.29 m²). It's used only in the US and Canada. Asphalt shingles are sold in bundles — 3 bundles typically cover one square (though some heavyweight shingles require 4 bundles per square). In the UK, Australia, and the rest of the world, all roofing materials are quoted per m².

## Frequently Asked Questions

A roofing square is 100 square feet (9.29 m²). It's used only in the US and Canada. Asphalt shingles are sold in bundles — 3 bundles typically cover one square (though some heavyweight shingles require 4 bundles per square). In the UK, Australia, and the rest of the world, all roofing materials are quoted per m².
A 6/12 pitch adds 11.8% more area than the footprint. A 9/12 pitch adds 25%. A 12/12 (45°) pitch adds 41.4%. Higher pitches also add labour cost because they're harder to work on safely. UK and Australian roofs are commonly steeper (35–45°) for rain runoff; US suburban homes commonly use 4/12–6/12 pitches for easier construction.

Source: https://worldcalculators.org/calculators/roof/
Markdown mirror of the HTML page. Prefer this URL for RAG; the interactive calculator still lives on the HTML page.