Metal Roof Cost Calculator
Find out how many metal panels are needed for your roof and calculate their cost in one go using this metal roof cost calculator.
The method
squares = sloped roof area ÷ 100 sq ft, plus waste
A square is 100 square feet
Roofing has been sold by the square for a century, and it means exactly 100 square feet of finished roof. Three bundles make a square for most three-tab and architectural shingles, though heavier products take four or five.
Measure the footprint and multiply by the pitch multiplier rather than trying to measure the slope from the ground. For a 6 in 12 roof over a 30 × 40 foot building that is 1,342 square feet, or about 13.4 squares before waste.
Ten per cent waste suits a simple gable. A roof with hips, valleys and dormers can easily need 15–20%, because every valley means cutting shingles at an angle.