Roof Truss Calculator

Spacing, Span & Quantity Required

The Roof Truss Calculator returns the number of pre-engineered roof trusses needed for a building based on its length, the on-center truss spacing (typically 24" o.c.), and the gable end overhang. Enter the length, spacing, and overhang and the tool calculates total truss count plus 2 gable-end trusses. Pre-fabricated trusses speed framing and provide engineered spans up to 60 ft. Pair the result with our Plywood and Underlayment calculators for a full new-build estimate.