A rigid structural element that extends horizontally and is supported at only one end. The anchored side resists the rotational force and bending moment created by the unsupported overhang. Builders use this principle to create balconies, deep roof eaves, and overhangs without needing exterior columns that would block walkways.
Heard on the job
The architect wants a four-foot cantilever on the front deck, so we'll need to upsize those joists.
Insider tip
A common rule of thumb for wood framing is that the backspan must be at least twice the length of the cantilevered section.