Roof Framing Ridge Board

Collar ties rafter ties tension beams structural ridge beams.

Roof framing ridge board.

The framing of a basic gable roof is based on a right angle triangle and the various roof framing components fit the triangle. For 2 x 4 rafters use a 2 x 6 ridge board. We will go over raft. A ridge board is a non structural member that serves as a prop for opposing rafters to rest against and connect to.

Wondering how to build the structure of your roof. A classic example is the los altos hills remodel below by klopf architecture which uses a double 2x tension tie to sandwich each roof joist. 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.

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. Essentially the spine of a conventional stick framed roof the ridge board is sandwiched between the meeting ends of the roof rafters. The ridge is the peak where two sloped roof sections meet. You may splice two boards together to achieve this length if necessary using a 14 and 1 2 inch block of the same material.

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. Traditional examples of the ridge board system utilize wood tension ties a k a. The run or half the building span is the base of the triangle. Collar ties of a similar dimension and look as the roof joists.

The finished ridge beam height z above the top of the wall will be m plus the y height. And the line length measurement from the roof peak to the building wall is the hypotenuse. Ridge beam sizing is based on the span of the beam between supports and the amount of roof load supported by the beam. Before you cut your boards you ll need to measure the width of your building and calculate the exact length of each rafter.

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. Determining the ridge beam height. If you know the slope x in 12 you want to use for your roof framing design you can use it along with the run r to determine the height of the ridge beam for example if the slope is 4 in 12 and the run is 12 feet the ridge beam height m will be 4 feet. This video covers one of the most exciting parts of roof framing installing rafters.

Ridge boards can only be used in roofs with slopes from 3 in 12 up to 12 in 12. The rise or height of the roof at its peak is the altitude of the triangle.