Roof Rafter Length Chart

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Roof rafter length chart.

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. 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. Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal. If you add an eaves overhang dimension then the amount the rafter sticks passed the wall will be added to the rafter length.

Calculate the length of a rafter from the roof slope ratio of inches per foot and a building width measurement. Here the number is 941 86 inches. Input the rafter span on the flat eave overhang and pitch of the roof. 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.

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. For example if the ridge beam is 1 5 inches thick subtract 3 4 of an inch from the overall rafter length. This calculator is to be used as an estimating tool only. The run of the rafter.

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. Height of the scaffold. The length of the rafter. 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.

Includes result for hip valley factor slope factor and the roof slope in degrees. 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. Roof rise this should be calculated from the base of the roof to the highest point of the roof gable the peak.