Ridge beam sizing is based on the span of the beam between supports and the amount of roof load supported by the beam.
Roof framing ridge board.
Wondering how to build the structure of your roof.
And the line length measurement from the roof peak to the building wall is the hypotenuse.
For 2 x 6 rafters use a 2 x 8 ridge board and so on.
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.
Part of a roof s frame a ridge board runs horizontally along the peak of a sloped roof.
Some of these can support the roof and prevent ridge sagging and wall spreading.
The roof rafters provide integral structural support to the roof.
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.
You may splice two boards together to achieve this length if necessary using a 14 and 1 2 inch block of the same material.
Traditional examples of the ridge board system utilize wood tension ties a k a.
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.
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.
We will go over raft.
The ridge is the peak where two sloped roof sections meet.
Before you cut your boards you ll need to measure the width of your building and calculate the exact length of each rafter.
Collar ties rafter ties tension beams structural ridge beams.
The rise or height of the roof at its peak is the altitude of the triangle.
Ridge boards can only be used in roofs with slopes from 3 in 12 up to 12 in 12.
Essentially the spine of a conventional stick framed roof the ridge board is sandwiched between the meeting ends of the roof rafters.
The finished ridge beam height z above the top of the wall will be m plus the y height.
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.
Collar ties of a similar dimension and look as the roof joists.
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.
A ridge board is a non structural member that serves as a prop for opposing rafters to rest against and connect to.
This video covers one of the most exciting parts of roof framing installing rafters.
