Roofing
Material quantity calculators using standard densities and coverage rates, with sensible waste margins.
Roof Pitch Calculator
Convert roof rise and run into pitch (X-in-12), angle in degrees, slope percentage and the rafter length multiplier.
Roof Area Calculator
Calculate true sloped roof area from building footprint and pitch, plus square feet, roofing squares and a waste allowance.
Shingle Calculator
Calculate asphalt shingle bundles and roofing nails needed from roof area and a waste allowance, using standard trade conventions.
Rafter Length Calculator
Calculate common rafter length from run and pitch (or rise), including the overhang converted to its along-the-slope length.
Metal Roofing Calculator
Calculate metal roofing panels and screws needed from roof area, panel coverage width and length, with an optional cost estimate.
Roof Snow Load Calculator
Estimate flat and sloped roof snow load from ground snow load, exposure, thermal condition and roof pitch, using the ASCE 7 flat-roof form.
Birdsmouth Cut Calculator
Calculate the heel depth of a rafter's birdsmouth cut from roof pitch and seat width, and check it against the remaining rafter depth.
Gambrel Roof Calculator
Size a classic gambrel (barn) roof with the circle method: equal rafter lengths, peak height, roof area and the 60°/30° slope pair from the building span.