In the picture above I'm measuring the top
of the stair stringer to find the width of the floor joist. If you look
at the tape measure closely you will notice that I'm at 11 1/2 inches.
This is the width of the floor joist, where I'm going to have the stair
stringer connect to the stair head out. These measurements are
important, when laying out your stair stringer's.
Split Level Stair Framing