Roof Truss Ridge Beam

Two king post trusses linked to support a roof.

Roof truss ridge beam. A timber roof truss is a structural framework of timbers designed to bridge the space above a room and to provide support for a roof. Our roots are in the manufacturing of glu laminated wood timbers offering glu laminated posts beams arches timber trusses bridges and pavilions. The difference between them is that a ridge beam is a structural member that bears half of the live and dead loads of the rafters on either side of it but a ridge board is not structural. So called because it is the horizontal beam that supports the ends of the rafters at the ridge.

The loads on the ridge beam are carried by vertical posts at the beam ends down through the building structural walls to the building foundation. Yes either a ridge board or a ridge beam is necessary and required by the building code where roof rafters meet at the the center of their span. A structural ridge beam is a horizontal beam placed at the peak or ridge of a roof and is designed to carry much of the live and dead loads or weight of the roof structure by itself. Ridge beams are required by code if the roof slope is less than 3 in 12 irc section r802 3.

Ridge beam sizing is based on the span of the beam between supports and the amount of roof load supported by the beam. It is often used to prevent separation of the rafters during high winds but can also be used simply to frame the ceiling. This is an example of a double roof with principal rafters and common rafters.