A little structural engineering lesson! Jettying is where upper level walls are shifted out beyond the area of the floor below. Beams supporting these walls have to be cantilevered out past the lower level walls. When a structure utilizes jettying - a negative bending moment is created which causes the beam to bend upwards. The positive bending moment from regular floor load is counteracted by the negative moment from the wall supported at the end of the cantilever. This can drastically reduce t