Roof Rafter Ridge Board

Before you cut your boards you ll need to measure the width of your building and calculate the exact length of each rafter.

Roof rafter ridge board.

The roof rafters provide integral structural support to the roof. Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal. Ridge boards can only be used in roofs with slopes from 3 in 12 up to 12 in 12. Ridge beam sizing is based on the span of the beam between supports and the amount of roof load supported by the beam.

The boards creating the slope of the roof are wider than lumber used to build trusses 2x8s 2x10s and 2x12s are most common in rafters vs. Rafters and a ridge board are the key components of a roof framing system. A ridge board is a non structural member that serves as a prop for opposing rafters to rest against and connect to. For 2 x 4 rafters use a 2 x 6 ridge board.

If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. Structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes. 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. This means that the ridge board for 2x6 rafters for example must be more than the nominal 6 inch height of the rafters because the diagonal cut at the ridge end of the rafter makes the vertical dimension of the face a larger dimension.

For 2 x 6 rafters use a 2 x 8 ridge board and so on. The ridge board s length will be the outside measurement of the building plus the length of the overhang at both ends. Some of these can support the roof and prevent ridge sagging and wall spreading. The rafters support the sides or slope of the roof.

Rafter boards are fastened to the ridge board at the peak and the top plate where they join the wall. It is always better to have a large rafter rather than be concerned with a sagging roof. A ridge board was not always required and the photo above of the attic in a 1920s era house shows a roof. In finished space insulation is placed between the rafter boards and drywall or other material is fastened to the face.

This article describes and illustrates the different types of support that prevents roof sagging and wall bulging at buildings including definitions of collar ties rafter ties and structural ridge beams. The ridge board forms the peak and ties the rafters together side to side and end to end. Choose a ridge board that is one size larger than your common rafters. This video shows how to make roof rafters with a rafter square and or a speed squ.