Roofing Square Count Calculator

1 roofing square = 100 ft². Bundles = squares × 3 (for 3-tab) or × 4 (architectural).

Inputs

Including pitch — measure on the roof, not footprint.

Result

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General calculation reads

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How to use this calculator

  • Enter actual roof surface area.
  • Pick shingle type.
  • Read bundle count.

About this calculator

Roofers think in "squares" — a square = 100 ft². 3-tab shingles cover a square with 3 bundles; architectural with 4; premium with 5+. Waste includes ridge/hip caps, broken pieces, and learning curve. Roof area is on-the-roof area (not building footprint) — multiply footprint by pitch factor (typically 1.05-1.41).

Frequently asked

How do I find roof area from footprint?+
Multiply footprint × pitch factor: 4/12 → 1.054, 6/12 → 1.118, 8/12 → 1.202, 12/12 (45°) → 1.414.
3-tab vs architectural shingles?+
3-tab: cheaper, ~20-year warranty, flat profile. Architectural: ~30-year, dimensional look, 50% more bundles.
What's underlayment?+
Felt or synthetic underlay between deck and shingles. 1 roll typically covers 4 squares.
Ridge cap shingles?+
Separate purchase. ~1 bundle per 35 LF of ridge.
Why 10-15% waste?+
Cut shingles around penetrations, ridge/hip cuts, breakage. Steeper roofs and more dormers = more waste.

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