Roofing
squares · bundles · underlaymentRoofing Squares
Convert roof footprint and pitch into roofing squares (100 sq ft each), with a waste factor for cuts and overlap.
Shingle Bundles
Estimate shingle bundles needed (3 bundles per square, standard 3-tab/architectural), auto-filled from your roofing squares.
Underlayment Rolls
Estimate felt or synthetic underlayment rolls needed to cover the roof, based on total roofing squares and roll coverage.
Planning a Roofing Project
Roofing material takeoffs start with converting your roof's flat footprint into actual sloped surface area, since a steeper roof has significantly more surface to cover than its footprint suggests. From there, shingles and underlayment are ordered by the "square" — the roofing industry's standard 100 sq ft unit.
How These Calculators Work Together
Start with the Roofing Squares calculator, entering your roof's footprint and pitch to get your total roofing squares. That number automatically carries into the Shingle Bundles calculator, and can be entered into the Underlayment Rolls calculator as well, so you only have to do the pitch math once for both material orders.
Frequently Asked Questions
Why do shingles and underlayment need separate calculators?
Shingles and underlayment come from different manufacturers with different coverage rates per package — shingle bundles cover a fixed fraction of a square (usually 1/3), while underlayment rolls cover a much larger area per roll. Both start from the same roofing squares total but scale differently.
Does roof complexity affect the estimate?
Yes — these calculators assume a simple footprint-times-pitch conversion. Roofs with hips, valleys, dormers, or multiple pitches need a higher waste factor (or a full roof-plane measurement) to account for the extra cutting and material loss that simple gable roofs don't have.