Roof Pitch Rafter Length Formula

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.

Roof pitch rafter length formula.

If you plan to have overhang etc. Includes result for hip valley factor slope factor and the roof slope in degrees. Roof pitch refers to the slope which the rafter creates. Our roof rafter calculator tools are handy for calculating the number of rafters needed rafter length calculator lineal feet of rafter board feed in ridge and sub facia and the total board feet in the roof.

All we do now is use a calculator to multiply 1 610 by the measurement in the book. In this example the shorter walls are 14 feet long. Determine a thickness for the ridge and use the drop down to select it. Input the rafter span on the flat eave overhang and pitch of the roof.

Roof pitch is simply the slopecreated by the rafter. Area span on the flat please enter area span on the flat in foot. Pitch is the incline of the roof represented as the ratio of rise to the span twice the run. 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.

Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal. The length of rafter per meter of run is 1 1543. If you add an eaves overhang dimension then the amount the rafter sticks passed the wall will be added to the rafter length. This means that for every 1m the rafter travels horizontally the angled length of the roof will be 1 1543m.

Often you express roof pitch as the ratio between the rise and the run in the form of x 12. Click the button to calculate the stock size needed for this job. Note that this is not the actual length of the rafter. It is the length of this portion of the rafter.

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. Roof pitch is often expressed as a ratio between rise and run in the form of x 12. Rafter length using pitch v r 2 sqrt 1 p 2 where v overhang r roof span p pitch. This calculator is to be used as an estimating tool only.

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. The results are automatically fired as soon as any of the values are entered or altered. The rafter member will be longer. 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.

Select a roof pitch. Rafter length calculator calculate the length of a rafter from the roof slope ratio of inches per foot and a building width measurement. 1 1543 x 1 610 1 858m.