You can sketch the extents of the area reinforcement boundary to show the bar length you want and place the overlaps where you want as well.
Simply overlap your sketches the correct amount.
However, to avoid creating perpendicular bars at the points where the sketches overlap, you will need to create two area reinforcements- One for each direction. Instead of using each area reinforcement to create 4 layers (top Major, Top Minor, Bottom Major, Bottom Minor) only check the "Major" Layers in the properties dialog. You can also provide an "additional offset"to keep the perpendicular bars from conflicting.
You may find it easier to control your reinforcement using an Area Reinforcements sketch rather than individual Rebar Sets.
Joe
