Gable Roof Ridge Beam

The rafters aren t trying to push the walls out.

Gable roof ridge beam.

A ridge beam is a structural member used to support the ends of the rafters at the ridge transferring it s loads to posts or gable end walls. The ridge board runs the length of the building and provides support for the tops of the rafters helping the whole roof structure work together as a system. Ridge beams are required by code if the roof slope is less than 3 in 12 irc section r802 3. The ridge board must be set as perfectly as possible so take your time and use careful measurements.

The typical gable roof diagram above shows the r length measured from the outside wall to the middle of the ridge beam the rafter section diagram below typical of a shed or patio cover roof shows the r length measured from the outside wall to the outside face of the ridge beam either one is acceptable depending on which type of roof you are building but if you are using the. The roof load is carried on the ridge and on the walls and there is no need for collar ties or ceiling joists to resist lateral thrust. In a roof with a ridge board there is lateral thrust. Putting it together is relatively straight forward if you have basic carpentry skills and use precise measurements.

To build your gable roof you ll need wooden boards cut into joists rafters supports and a ridge board in addition to sheathing felt paper and shingles. I can t ever recall seeing a saltbox shed built with a ridge beam or even a gambrel roof shed for that matter. Leave ridge beam for shed construction page.