Roof Rafter Length Chart

Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal.

Roof rafter length chart.

For example if the ridge beam is 1 5 inches thick subtract 3 4 of an inch from the overall rafter length. Rafter span tables use these tables to determine lengths sizes and spacing of rafters based on a variety of factors such as species load grade spacing and pitch. Includes result for hip valley factor slope factor and the roof slope in degrees. 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.

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. 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. Calculate the length of a rafter from the roof slope ratio of inches per foot and a building width measurement. Visit the roof framing page for more information on cutting roof rafters and visit the roof pitch calculator for determining rafter lengths based on rise and run.

Rafter run outer wall this should be measured starting from the center of the roof span and then extending to the very edge of the exterior wall. Here the number is 1166 66 inches. 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. This calculator is to be used as an estimating tool only.

Click the button to calculate the stock size needed for this job. The run of the rafter. Enter the value for the roof width outside to outside in feet inches and fraction inches and fraction or use the inches box to enter a value in decimals if that is your preference. Input the rafter span on the flat eave overhang and pitch of the roof.

Roof rise this should be calculated from the base of the roof to the highest point of the roof gable the peak. Here the number is 941 86 inches. The rise of the rafter.