Measure a roof
Start here for the numbers every roofing estimate depends on: pitch, area and squares.
Guides and calculators
Roof Pitch Calculator
Enter the rise and run to get your roof pitch, angle, grade and slope multiplier, with a pitch-to-angle chart and the formula shown.
Measure a roofHow to Measure Roof Pitch Without Going on the Roof
Three ways to measure roof pitch from the attic, a ladder or the ground, the math to convert your measurement, and worked examples.
Measure a roofRoof Area Calculator
Work out your roof's square footage and roofing squares from the house size, pitch and overhang, with the formula and a worked example.
Measure a roofHip Roof Calculator: Area, Ridge and Hip Lengths
Work out a regular hip roof's area, ridge length, hip length and eaves from its size and pitch, with the formula, a worked example and what it leaves out.
Measure a roofRafter Length Calculator
Enter your building span, roof pitch, overhang and ridge board to get rafter length in feet and inches, the rise, and the stock length to buy.
Measure a roofWhat Is a Roofing Square? Size, Conversions and Bundles
A roofing square is 100 square feet of roof. See how to convert your roof size to squares and bundles, and why roofers quote in squares.