Roof Rafter Framing Details

Rafters act more like the top chord of a roof truss than as a roof joist.

Roof rafter framing details.

Transfers the load of the roof through the raftersto walls below. The values on the calculator that we use for common roof framing are. Definition of collar tie in roof framing definition. Position the square at the end of the rafter board with the tongue on your left and facing away from you.

Using a construction calculator. Measure form the top of this line down the board to determine the line length or length of the rafter less the ridge. The point at which all the rafters are attached to. Roof framing terms are related to the parts of a triangle.

The rafters carry the applied loads to the exterior walls. Supported by lally columns. Not shown are the hip and valley rafters needed to tie the roof together where the rafters are framed at an angle to each other. Add the length of the overhang beyond this mark and.

If you have any two of those values the calculator will quickly figure out the rest of the right triangle which means it will tell you everything else you need to know about a rafter. Roof features associated with basic roof framing terms are shown in figure 2 2. Joists and collar ties. Cover some of the more common roof and rafter terms you ll need.

By upper third here we mean one third of the length of the rafter from ridge to top plate. In a rafter roof all of these components are required to provide a stable roof. Ridge beam sits below the rafters. The function of each component is.

Refer to the figure as you study the terms discussed in the next paragraphs. Parts of a roof a ridge board is a horizontal member of the roof frame.