Gable Roof Without Ridge Board

Ridge beams are required by code if the roof slope is less than 3 in 12 irc section r802 3.

Gable roof without ridge board.

In conventional gable roof framing the slope of the roof is formed by rafters that run diagonally downward from the peak of the roof to the tops of the exterior walls of the building. The ridge board s length will be the outside measurement of the building plus the length of the overhang at both ends. Its only job is to provide a connection point for the roof joists on each side of the roof. Ridge beam sizing is based on the span of the beam between supports and the amount of roof load supported by the beam.

Because the ridge board is a smaller member typically only an inch thick sometimes even less it is not a structural member and doesn t carry the gravity load. It s often just a nice way to bring the rafters together. You don t need a ridge beam but you do need a way to keep the walls from spreading. The picture above shows the plan view of a gable roof ladder trusses are made up using four noggins bridging at each corner to support a rafter outside the building.

A ridge board is a non structural member that serves as a prop for opposing rafters to rest against and connect to. A ridge board isn t a beam per se. Framing a gable roof building a gable with barge end purlin struts and collar ties. For 2 x 6 rafters use a 2 x 8 ridge board and so on.

That rafter outside forms the overhang for the barge boards to fix to and so the soffit boards and ventilation are continuous all the way. For 2 x 4 rafters use a 2 x 6 ridge board. Choose a ridge board that is one size larger than your common rafters. A proper beam would have a supporting post at each end.

In this design the tops of the rafters attach to a load bearing ridge beam that runs along the length of the roof. Ridge board the engineering principles of the ridge board are a bit more complicated. 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. Putting it together is relatively straight forward if you have basic carpentry skills and use precise measurements.