Gable Roof Ridge Board

Rafters and ridge boards.

Gable roof ridge board.

Ridge beams are required by code if the roof slope is less than 3 in 12 irc section r802 3. Putting it together is relatively straight forward if you have basic carpentry skills and use precise measurements. Ridge beam sizing is based on the span of the beam between supports and the amount of roof load supported by the beam. The ridge board must be set as perfectly as possible so take your time and use careful measurements.

After they re up you can snap a line to mark and trim the tails in a nice straight line to make up for any ridge warp or marking cutting and fixing errors. If you re framing a gable roof on a new house or building a shed or even a doghouse with a gable roof you ll need to cut a number of roof rafters. 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 rafters provide integral structural support to the roof.

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. 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. 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. 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.

In part 3 of our roof framing series we cover how to select a ridge board how to layout a ridge board how to mark it so you know where to fasten the raft. Ridge board the engineering principles of the ridge board are a bit more complicated. A ridge board is a non structural member that serves as a prop for opposing rafters to rest against and connect to. 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.

Gable roof framing calculator plan diagram with full dimensions for a good straight fascia add an extra inch or 2 to the tails of all your rafters total length. Before you cut your boards you ll need to measure the width of your building and calculate the exact length of each rafter. Its only job is to provide a connection point for the roof joists on each side of the roof.