Woodworking Definition: OC (On-Center)

Builder Hammering Roof Truss Nail Against Blue Sky
BanksPhotos Getty Images

Definition

The term "ON-CENTER," which is often abbreviated "OC," refers to measuring components of a woodworking or construction projects according to where the center of the stock's thickness falls.  For instance, in framing a residential wall, a building plan may call for the wall studs to be placed every 16 inches OC against the floor plate and top plate. This means that the center of each stud is placed at intervals of 16 inches.

OC measurements are important, as building codes may have particular stipulations for the intervals of framing members, such as studs, rafters, ​and floor joists.