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Roofing Calculator

Calculate roofing squares, shingle bundles, and underlayment from roof area.

Inputs

Results

Roofing squares22squares
Shingle bundles66bundles
Underlayment615 lb rolls
Roofing nails7,040nails

Estimates only — verify against project conditions and manufacturer data.

Good to know

  • A "square" is 100 sq ft of roof; most architectural shingles run 3 bundles per square.
  • Roof area is the actual sloped area, not the building footprint — multiply footprint by a pitch factor.

From one trade to all of them

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PreCal-IQ reads your specs and plans together and generates complete takeoffs across 45 CSI categories — automatically. Skip the manual math on every line.

FAQ

Common questions

How many bundles of shingles per square?

Most architectural (laminate) shingles are packaged 3 bundles per square (100 sq ft). Some heavier shingles run 4 bundles per square.

How do I find roof area from the footprint?

Multiply the footprint by a pitch factor — about 1.12 for a 5/12 pitch, 1.20 for 7/12, 1.25 for 8/12 — then add waste.

Stop calculating one trade at a time

PreCal-IQ generates full takeoffs across 45 CSI categories from your specs and plans. Request a demo on your own project.