Gutter Length Calculator
Adds a 10% waste allowance to the raw eave perimeter length to account for corner miters, end caps, and overlap joints.
Roof Area Calculator
Roof area pitch multiplier = sqrt(1 + (rise/run)²), applied to the flat building footprint to find the true sloped roof surface area.
Roof Pitch Calculator
Pitch is expressed as "X/12" (rise per 12 in of run); angle in degrees = atan(rise/run).
Roof Rafter Calculator
Rafter length = run / cos(pitch angle); rafter count = ceil(building length ft x 12 / spacing in) + 1, at standard 16 in or 24 in OC.
Roof Shingle Calculator
Standard asphalt shingles: 1 roofing square = 100 sq ft = 3 bundles (33.3 sq ft/bundle); 10-15% waste is added for cuts, hips, valleys, and ridges.
Roof Slope Calculator
Slope % = (rise/run) x 100; angle in degrees = atan(rise/run) — the same rise-run geometry as pitch, framed as a percentage grade rather than X-in-12 notation.
Roof Truss Calculator
Truss count = ceil(building length ft x 12 / spacing in) + 1, using standard 24 in OC (or 16 in OC) truss spacing.
Roofing Material Calculator
Combines shingle bundles (3/square, 33.3 sq ft/bundle, +10-15% waste), underlayment rolls (standard felt #15 ≈400 sq ft/roll, synthetic/ice-and-water ≈200 sq ft/roll — adjustable), and roofing nails (~320 per square).