How To Find Roof Pitch And Rafter Length

The value displayed as the rise will be your x.

How to find roof pitch and rafter length. Pitch is the incline of the roof represented as the ratio of rise to the span twice the run. For example a rafter installed at a 4 12 pitch rises 4 feet for every 12 feet from an outside wall. 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. For example a roof that rises 6 inches for every 12 inches of horizontal run has a 6 12 pitch.

Use the blueprints to establish a pitch for the roof. Determine a thickness for the ridge and use the drop down to select it. How do you calculate a roof pitch. To establish the rafter length we calculate the following.

If you add an eaves overhang dimension then the amount the rafter sticks passed the wall will be added to the rafter length. Includes result for hip valley factor slope factor and the roof slope in degrees. It is the length of this portion of the rafter. Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal.

Roof slope calculator example of use measure the run length it is the horizontal distance between the roof ridge and the wall of the building. 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. After entering all of the values the roof pitch calculator automatically gives you the values of the roof pitch roof pitch and roof pitch x 12. There is no standard universal pitch of roof.

The second number is the benchmark for typical pitched roof calculations. If you want to find the roof pitch in the form of x 12 simply calculate the pitch and substitute 12 for the run length. Rafter length using angle v r 2cos a rafter length using pitch v r 2 sqrt 1 p 2 where v overhang r roof span p pitch 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. The first number represent the amount in feet that a rafter rises.

4 8 2 2 4 for one half of your roof s width b skip this step if you already know what measurement half the width of your roof is. If you plan to have overhang etc. 2 4 x 1 1034 refer to image to the right 2 65 2 175m is your rafter length. Select a roof pitch.

It varies depending on culture climate style and available materials. Note that this is not the actual length of the rafter. 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. The results are automatically fired as soon as any of the values are entered or altered.

The rafter member will be longer.