Squares, bundles and pitch
Roofers measure in "squares" — one square covers 100 square feet. Asphalt shingles come 3 bundles to the square. Because a pitched roof has more surface than the footprint it sits on, we multiply by a pitch factor, then add 10% for waste, ridge caps and starter strips. Installed prices include tear-off, underlayment and labour; materials alone are far less.
A complex roof with many valleys, dormers or hips uses more material than this simple estimate.
Price guidance is a US 2026 market range gathered from public cost guides, shown in US dollars regardless of the currency you select above. Real prices vary widely by region, grade and supplier — always use your own quote.