Roof Ridge Beam Span Calculator

Enter these values and these results are automatically fired the length of the rafter the run the rise and the height of the scaffold.

Roof ridge beam span calculator.

Use the span tables below to determine allowable lengths of joists and rafters based on size and standard design loads. 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. For example if the ridge beam is 1 5 inches thick subtract 3 4 of an inch from the overall rafter length. Loading conditions are detailed below.

Also available for the android os. Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal. If you are calculating rafter length from the center of the ridge beam as shown below you will need to subtract half of the thickness of the ridge beam from the top end of the rafter. Span calculator for wood joists and rafters also available for the android os.

This calculator matches up with 90 of the applications in the 2012 international residential code book. It has been my experience to never use a beam smaller than a two ply 2 x 8. Refer to sfpa s publication southern pine headers beams download in publications that includes all size selection and allowable load tables. For each application a pdf download is available.

Use this common rafter caclulator by entering the span the roof pitch and the ridge thickness. You can also use the wood beam calculator from the american wood council website to determine maximum rafter and joist lengths. Also see assumptions for table development.