Simple roofs, such as a shed or the common gable, are fairly easy to construct, even without plans, if you understand the basics and a little geometry. A framing square is used to lay out the rafters. Keep the framing square in the position that it was set in to measure the birdsmouth cut.
Having the correct pitch is important. Warnings Always take safety precautions when working with any type of saw. This tool takes a lot of the figuring and guessing out of creating hips and valleys. The long adjustable edge represents the hypotenuse of the triangle, or the line length. The roof rafters provide integral structural support to the roof. Latest Videos. They are notched to fit around the gable-end rafters.
So, use a tape measure to find the height of the roof above the top wall of the building. Co-Authored By:.
Hold the long end of the framing square so that the other stair gauge is also resting against the rafter; this will ensure that you mark the tail cut at the correct angle. To measure pitch, first position the hypotenuse of the square on the roof, running straight up the pitch. Position the square with the base or raised edge on top of the rafter board.
After all, silicones are famous in uses as diverse as medical implants to industrial lubricants. Start this measurement from the top the long end of the cut you just made.
The new C. After you determine the rise, span, run, line length and pitch, the next step is to lay out the rafters, or mark the cuts on a pattern rafter to create the roof. Determine the rafter overhang, move the square to that position and make another plumb cut mark.