Roofing Calculator

Calculate total roof surface area, roofing squares (100 sq ft), and required shingle bundles based on house footprint and roof pitch.

How to use this calculator

1. Enter house footprint.
2. Select pitch.
3. Read roofing squares and shingle bundles.

Formula & method

Pitch Multiplier Model

Roof Area = Footprint × Pitch Multiplier

Pitch slope multiplier.

Example

40x30 footprint @ 4/12 = 14.5 squares with waste.

Key insights

• 1 Square = 100 sq ft.
• 3 bundles = 1 square.

How to interpret your result

Roofing Squares

Unit for purchasing shingles.

Frequently asked questions

Bundles per square?

3 bundles per square.

Related calculators

• Square Footage Calculator — Calculate area in square feet or square meters for rooms and lots.
• Tile Calculator — Calculate total floor/wall tiles needed and number of boxes to purchase.

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