Floor Joist Cantilever Design

Instead of separate tables for non cantilevered and cantilevered joists a single proposed table provides maximum joist span and cantilever distances for all conditions which should simplify joist specification without compromising design freedom.

Floor joist cantilever design.

Cantilevered joists in an enclosed space. Cantilevered floor joists h1 2 treated l. The distance your joists can safely cantilever or overhang a drop beam is determined by the size of the joists the wood type and grade of the lumber and the spacing between joists. Branz recommends that all cantilevered joists have continuous blocking.

Similar to joists beams can cantilever up to one fourth their backspan. Many building departments limit joist cantilevers to 24 maximum. 2 the cantilevered portions referred to in sentence 1 shall not. The ontario building code cantilevered floor joists 9 23 9 9.

At the line of the cantilever support wall. See section r301 2 2 2 5 item 1 for additional limitations on cantilevered floor joists for detached one and two family dwellings in seismic design category d 0 d 1 or d 2 and townhouses in seismic design category c d 0 d 1 or d 2. A full depth rim joist shall be provided at the unsupported end of the cantilever joists. Cantilevered floor joists 1 floor joists supporting roof loads shall not be cantilevered more than 400 mm beyond their supports where 38 mm by 184 mm joists are used and not more than 600 mm beyond their supports where 38 mm by 235 mm or larger joists are used.

Cantilevers parallel to joist direction in this situation while the open web joist stops at an exterior bearing a 2x extension from it extends beyond the bearing to become the cantilever joist.