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Asphalt Shingle Roofing Cost Calculator

6run 12pitch 6/12 · slope factor 1.118
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1,341.64 sq ft of roof

13.42 squares (roof area 1341.64 sf = footprint × 1.12 slope factor); 1475.8 sf with 10% waste.

45 bundles (OC-class 32.8 sf/bundle, whole-bundle round-up).

Typical crew rate for this trade: $37-$61/hr (modeled from BLS median wage × published burden/markup band). How we model costs.

Reference material price: Owens Corning Oakridge Architectural Shingles (32.8 sf/bundle), $44.97/bundle (typical retail, sampled 2026-08-15; local prices vary). How we model costs.

  • Sloped area = footprint × √(1+(rise/12)²) = 1200 × 1.12. Pure geometry: include eave/rake overhangs in your footprint or this understates.
  • Waste: 10% for simple gable (JLC convention). Waste is a range by design; cut-up roofs can exceed 15%.
  • Footprint estimation fails on complex plans (dormers, turrets, intersecting gables); measure each roof plane there instead.
  • A 4/12-vs-8/12 pitch mistake is a 14% area error: verify pitch, don't guess it.
  • Bundles: whole-bundle round-up at 32.8 sf/bundle (product-specific, OC Oakridge TDS). 3 bundles/square mainstream.

Want quotes from local pros for this project? We’re gauging demand for a pro-matching service. No contractor network exists yet: this is a get-notified list, not a quote request.

Why This One Is Different

Every "cost per square" number you find for a reroof online seems to disagree with the next one, and that's not because someone's padding the estimate. This calculator prices the material takeoff exactly and models labor as a band, instead of blending both into one falsely precise total. The material side is the easy part to price exactly: a 24-square gable roof needs about 72 bundles of architectural shingles at 3 bundles per square, and once you know the product and its bundle price, that line item is arithmetic, not guesswork. The labor line is where those online estimates diverge by 2-3x across regions, almost never because contractors are padding margins: it's burdened wage (statutory costs, workers' comp, insurance) times a markup range that genuinely differs by state and company.

Where the Numbers Come From

  • Mainstream architectural shingles run 3 bundles/square (~32.8-33.3 sf/bundle); material cost is bundle count × current bundle price, the one exact line item in a reroof estimate. Source: GAF Timberline HDZ spec sheet (3 bundles/square); OC Oakridge TDS (32.8 sf/bundle)
  • Shingle waste runs ~10% simple gable, 15%+ cut-up (hips/valleys), applied to the field-shingle bundle count before pricing, not to accessories. Source: JLC, Asphalt Shingles Field Guide (trade convention)
  • Labor is burdened wage (statutory adders + workers' comp + insurance, ~1.2-1.4× open shop, up to ~1.7× union) marked up to a charged rate (~1.5-2.5×, per NAHB-measured builder/remodeler margins), never a flat national $/square figure. Source: IRS Topic 751; BLS Employer Costs for Employee Compensation; NAHB Cost of Doing Business via Eye On Housing (see /methodology/)
  • Rounding always favors having a bundle left over, not a bundle short: worked example: 24 squares × 1.10 waste = 2,640 sf ÷ 32.8 sf/bundle (OC Oakridge TDS, the engine's constant) = 80.5 → 81 bundles, rounded up to the next whole bundle. Source: worked example (matches the calculator's 32.8 sf/bundle TDS constant)

More Questions

Why do asphalt shingle roofing quotes vary so much?

Mostly the labor side: workers' comp class rates, wage levels, and target margins differ by region and company, often by 2-3x. Material cost should be similar everywhere for the same product; labor is where estimates genuinely diverge.

Related Calculators

Formulas, waste factors, and cost models on this page follow the sourced conventions on our methodology page. Estimates only; verify with your supplier and local code.