Roofing Squares Calculator (Footprint + Pitch)

One square equals 100 ft² of roof surface. Enter the building’s plan footprint, pick a pitch (or type your own multiplier from the pitch tool), and add a waste factor if you are ordering material.

Results

Roof surface area—

Squares (exact)—

Squares with waste—

Suggested order (round up)—

Assumes a single plane or a simple gable equivalent. Dormers, hips and valleys need more waste and real field measurement.

Formulas used

multiplier = √(1 + (rise/12)²)   for an X:12 pitch
roof_ft²   = footprint_ft² × multiplier
squares    = roof_ft² / 100
with_waste = squares × (1 + waste% / 100)
order_up   = ceil(with_waste)    for rough material planning

Worked example: a 2,000 ft² footprint at 6:12 (multiplier 1.118) gives 2,236 ft², or 22.36 squares; at 4:12 (1.0541) it gives 21.08 squares, and +10% waste takes that to 23.19 — order 24.

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