Roof truss calculator

The Roof Truss Calculator is a practical estimation tool designed to help homeowners, builders, and roofing professionals calculate basic roof truss dimensions quickly and accurately.

Roof Truss Calculation Method

The calculation method is based on standard roof framing geometry. The calculator first divides the total building span in half to determine the half-span. Using the selected roof pitch (expressed as X/12), it calculates the ridge height (rise) by multiplying the half-span by the pitch ratio. The rafter length is then calculated using the Pythagorean theorem, treating the roof structure as a right triangle.

These results provide a reliable estimate for roof framing layout, material planning, and educational purposes. For structural accuracy and safety, final truss designs should always be reviewed by a qualified professional before construction.