Roof Pitch Rafter Length Formula

1 1543 x 1 610 1 858m.

Roof pitch rafter length formula. Use our online rafter length calculator to quickly compute the length of the shed roof rafter by entering the measurements of overhead length of roof span pitch or angle. In this example the shorter walls are 14 feet long. The length of rafter per meter of run is 1 1543. For example if the roof rises 4 feet and the span is 16 feet twice the run then the pitch is 4 16 or 1 4.

Roof pitch is simply the slopecreated by the rafter. Rafter length calculator calculate the length of a rafter from the roof slope ratio of inches per foot and a building width measurement. All we do now is use a calculator to multiply 1 610 by the measurement in the book. It is the length of this portion of the rafter.

You can assess this in two ways either as the roof pitch angles which the rafters make with the horizontal or the proportion between the run and the rise of the roof. Divide this in half and the result is 7 feet. Use the blueprints to establish a pitch for the roof. If you plan to have overhang etc.

All you need to know are the span of the building and the slope of the roof. The rafter member will be longer. Includes result for hip valley factor slope factor and the roof slope in degrees. Select a roof pitch.

Note that this is not the actual length of the rafter. The results are automatically fired as soon as any of the values are entered or altered. If you add an eaves overhang dimension then the amount the rafter sticks passed the wall will be added to the rafter length. The length of the rafter is given from the long point of the ridge cut at the top down along the top edge the board to the same plumb cut on the rafter s notch.

Rafter length using pitch v r 2 sqrt 1 p 2 where v overhang r roof span p pitch. Often you express roof pitch as the ratio between the rise and the run in the form of x 12. When building a roof how do you calculate the length of the rafters. Pitch is the incline of the roof represented as the ratio of rise to the span twice the run.

Determine a thickness for the ridge and use the drop down to select it. Roof pitch refers to the slope which the rafter creates. It can be assessed in two ways either as the angle the rafter makes with the horizontal or the proportion between the rise and the run of the roof.