Direct Answer
A work point (WP) is the theoretical intersection of member centerlines at a connection — the reference point from which all connection dimensions are measured. On shop drawings, dimensions are typically given 'work point to work point' rather than to physical faces or ends, because the WP is a consistent geometric reference regardless of member size.
Full Explanation
For a beam framing into a column, the work point is where the beam's centerline intersects the column's centerline — not where the flange faces touch. Dimensions from WP to the end of the beam (the 'setback') account for the half-depth of the column and any gap requirements. When a beam is skewed or sloped, the WP becomes even more critical because the setback dimension changes with angle. The detailer computes all setbacks from WP geometry in the 3D model; the fabricator must understand this reference to verify dimensions correctly.
What This Means for Your Shop
When verifying member lengths against the shop drawing, always check whether the dimension given is WP-to-WP (longer than the physical member) or face-to-face (shorter). Using the wrong dimension reference to check a member length is a common source of dimension confusion.
Common Mistakes
Measuring a beam length end-to-end on the shop floor and comparing to a WP-to-WP dimension on the drawing without applying the setback correction. The member will always appear 'short' by the sum of the setbacks at both ends.
Recommended Process
On your piece mark drawing review checklist, note whether the dimension callouts are WP, face, or end dimensions. Train your layout staff to apply the correct reference before measuring. When in doubt, call the detailer for clarification rather than guessing.