Rafter

Definition

A rafter is a framing member that runs up and down the slope of a pitched roof. The beams that slope from the ridge of a roof to the eaves make up the main body of the roof's framework.

Purpose

The purpose of a rafter is to support the roof decking and roofing materials, transferring the load to the walls and providing the main structural framework for a sloped roof.

Examples of Use

• Rafters are used in residential and commercial buildings with pitched roofs to create a strong, supportive structure.
• In traditional timber framing, rafters form the primary support for the roof covering.
• Rafters are essential in gable, hip, and gambrel roof designs, providing the necessary support and shape.

Related Terms

• Common Rafter: Rafters that run perpendicular to the wall plate and extend to the ridge.
• Ridge: The horizontal line at the top of the roof where the rafters meet.
• Eaves: The edges of the roof which overhang the face of a wall.

Notes

Rafters must be properly sized and spaced to ensure the roof's structural integrity and ability to withstand loads such as snow, wind, and roofing materials.