Free tool

Roofing calculator

Enter the building footprint and pitch to get roof area, squares, waste, and a bundle-by-bundle material takeoff.

Roof inputs

Roof surface area
2,012.4 ft²
Pitch multiplier
×1.118
Measured squares
20.12
Squares to order
22.54

Material takeoff

Planning quantities for an architectural shingle system. Confirm against your supplier's coverage rates.

Shingle bundles (3 per square)
68
Synthetic underlayment rolls (10 sq)
3
Starter bundles (100 lf)
2
Ridge-cap bundles (20 lf)
4
Drip edge sticks (10 ft)
23
Ice-and-water rolls (65 lf)
3
Coil nail boxes
2

How roofing squares are calculated

A roofing square is 100 square feet of roof surface — not floor area. Because a roof is sloped, its surface is always larger than the footprint underneath it. The conversion is the pitch multiplier: a 6/12 roof over a 1,800 ft² footprint covers about 2,012 ft², or roughly 20.1 squares.

Waste factor covers starter cuts, hip and valley cuts, and damaged bundles. Simple gable roofs run about 10%; cut-up hip roofs with multiple valleys often need 15% or more. Order on squares with waste; price tear-off on measured squares.

Keep going

Send this as a branded proposal instead.

RoofBid turns these numbers into a homeowner-ready proposal with your logo, your pricing, and e-signature — in about two minutes.

No credit card · First 3 proposals free