Roof Rafter Length Chart

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.

Roof rafter length chart.

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. Here the number is 1166 66 inches. Calculate the length of a rafter from the roof slope ratio of inches per foot and a building width measurement. 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.

The length of the rafter. Includes result for hip valley factor slope factor and the roof slope in degrees. The run of the rafter. If you add an eaves overhang dimension then the amount the rafter sticks passed the wall will be added to the rafter length.

For example if the ridge beam is 1 5 inches thick subtract 3 4 of an inch from the overall rafter length. Roof rise this should be calculated from the base of the roof to the highest point of the roof gable the peak. Click the button to calculate the stock size needed for this job. Input the rafter span on the flat eave overhang and pitch of the roof.

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 941 86 inches. 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. 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.

The rise of the rafter. This calculator is to be used as an estimating tool only. 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.