Roof Joist Length Calculator

Understanding Roof Framing

Proper measurements ensure structural integrity.

  • Roof Pitch Slope determines length.
  • Bird's Mouth Seat cut for wall support.
  • Overhang Extension beyond walls.
  • Ridge Height Peak elevation factor.

Common Roof Styles

Gable

Triangle-shaped end

Hip

All sides slope

Shed

Single slope

Valley

Intersecting roofs

Installation Tips

  • Layout Mark rafter positions.
  • Cutting Use proper angles.
  • Spacing Follow code requirements.
  • Support Ensure proper bearing.