Roofing calculators.
Measure supplied roof planes and order materials using effective coverage. These tools do not set roof structure, pitch or fixing requirements.
Choose a work subcategory
Roof Plane Area Calculator
Sum the geometric area of specified roof planes from horizontal run, rise and ridge length.
Open calculatorRoofingRoof Covering Units Calculator
Count effective roof-covering rectangles per plane and separately specified ridge-cap units.
Open calculatorRoofingRoof Membrane Roll Lap Calculator
Count membrane courses and rolls for supplied roof-plane dimensions and specified side and end laps.
Open calculatorRoofingRidge Cap Effective Cover Calculator
Count cap pieces across supplied ridge runs using the effective exposed length after specified overlap.
Open calculatorRoofingGutter Run Stock Calculator
Count standard gutter lengths and supplied fittings across separate runs.
Open calculatorRoofingSoffit Strip Cut Quantity Calculator
Count soffit strips cut across an overhang, using full source lengths and the installed strip coverage width.
Open calculatorRoofingEqual-Pitch Hip Roof Geometry Calculator
Combine two trapezoidal and two triangular planes of a specified symmetric hip roof.
Open calculatorConnect these calculations
Measure and check your purchase assumptions
Keep a hip roof’s plan dimensions separate from sloped plane dimensions
Why is rectangular plan area smaller than a supplied four-plane roof surface?
Read guideguideKeep nominal roofing dimensions separate from effective coverage
Does the whole product rectangle cover the same usable roof area?
Read guideguideDo not pool ridge lengths without checking cap cuts and overlaps
Does the sum of short ridge runs prove a whole-piece purchase count?
Read guideguideGutter stock quantity does not establish drainage capacity
What does a run-length and fitting takeoff leave unanswered?
Read guideguideAccount for both side and end laps in roof rolls
Which two overlap directions affect a rectangular membrane order?
Read guideguideCompare ridge cap physical and exposed length
Why is exposed length the correct increment after the first cap?
Read guideguideSeparate gutter stock and fitting schedules
Which fittings can be inferred from straight stock joins and which must be supplied?
Read guide