Roof Rafter Span Lengths

Determine the camber along the timbers length.

Roof rafter span lengths. With the tape measure hooked onto the top end transfer your two rafter lengths onto. Rafter spans can be extended slightly beyond what the rafter tables suggest when there is a cantelever extending beyond the supporting wall. Here the number is 941 86 inches. Marking out the roof rafter lengths onto the timber before cutting step 1.

Here the number is 1166 66 inches. Roof rise this should be calculated from the base of the roof to the highest point of the roof gable the peak. Before you can mark the rafter lengths and layout check the. Area span on the flat please enter area span on the flat in foot.

This calculator is to be used as an estimating tool only. 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. Ceiling joist span use this table to determine the maximum lengths of ceiling joists based on species of lumber joist spacing and joist size. 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.

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. Mark the plumb cuts.