Standards-compliant calculators for roofers in NZ & Australia. Free, no signup required. Works on mobile.
Each calculator opens on its own page — bookmark the ones you use most.
Pitch in degrees, actual slope area, rafter and ridge lengths for gable, hip and skillion roofs.
Corrugated, Trafco, standing seam. Sheet count with waste allowance and weight estimate.
Size gutters and downpipes per NZS 3500.3. Design rainfall for 8 NZ and AU cities.