Framing & Roofing Calculators
Rafters, roof pitch and lumber.
Roof and lumber calculators depend on one upstream number: pitch. Rafter length, roof area, and board requirements all scale with how steep the roof is, so if you don’t already know your roof’s pitch, start with the Roof Pitch Calculator before using the others in this category — guessing the pitch is the most common way these estimates end up wrong.
Rafter Calculator
Find rafter length from building width, pitch and overhang.
Roof Pitch Calculator
Convert rise and run into pitch notation, angle and slope percent.
Roofing Calculator
Estimate roofing squares and shingle bundles from building dimensions and pitch.
Board Foot Calculator
Calculate board feet and lumber cost from thickness, width and length.
Insulation Calculator
Estimate insulation bags needed by area and R-value for walls or attics.