FIELD GUIDE • UPDATED SEPTEMBER 2026
Rolling Offset Bending Guide
Calculate true offset, bend spacing, and roll angle when conduit moves two directions.
A rolling offset moves conduit vertically and sideways at the same time. Treat the vertical rise and sideways roll as the legs of a right triangle. The diagonal is the true offset.
Field method
Calculate true offset with the Pythagorean relationship: square the rise, square the roll, add them, then take the square root. Multiply the true offset by the selected bend-angle multiplier to get the distance between bend marks.
The rotation or roll angle can be found from the relationship between the sideways movement and vertical rise. In the field, accurate reference lines are essential. Mark the conduit and the bender so both bends stay in the intended plane.
Common mistakes
Example: a 6-inch rise and 8-inch sideways roll form a 10-inch true offset. With 30-degree bends, the 2.0 multiplier gives 20 inches between marks.
Common mistakes include multiplying only the vertical rise, using the diagonal as one of the legs, rotating the second bend the wrong direction, and measuring from different reference surfaces.
Use the WireWise rolling-offset calculator to produce true offset, spacing, rotation, bend marks, and estimated total conduit length. Confirm actual shoe gain and job clearances before cutting.