What are the limits of cantilever beams?
Table 8.4.2.2AITC Deflection Limits for Uses WhereIncreased Floor Stiffness is DesiredUsed with PermissionUse ClassificationApplied Load OnlyApplied Load + Dead LoadaFloor Beams- Commercial, Office & Institutional- Floor Joists, spans to 26 ftb - LL < 60 psfL/480L/360 - 60 psf < LL < 80 psfL/480L/360 - LL > 80 psfL/420L/300- Girders, spans to 36 ftb - LL < 60 psfL/480L/360 - 60 psf < LL < 80 psfL/420L/300 - LL > 80 psfL/360L/240aThe AITC includes a modifier on DL depending on whether or not the timber is seasoned.bFor girder spans greater than 36 ft and joist spans greater than 26 ft, special design considerations may be required such as more restrictive deflection limits and vibration considerations that include the total mass of the floor.The span length, L, in the limit equations above is taken as the distance between center of supports. For cantilever beams, a value equal to twice the actual cantilever length is generally used for the L in determining the deflection limits
