a. Rise Height. In order to determine the height of the risers, use a set of dividers and set them at 7 inches. Now step off the distance on the story pole from one end of the pole to the mark you made on the other end. If the distance will not divide into the length of the story pole evenly, adjust the divider spans slightly and again step off this distance on the story pole. Continue adjusting and stepping off until the story pole is marked off evenly. Now count the number of spaces stepped off. This will be the total number of risers in the stairs.

b. Stairway Length. Measure the length of the stairwell for the length of the run of stairs. The length may also be obtained from the details on the pane.

c. Tread Width. To determine the width of each tread, divide the number risers, less one (remember there is one more riser than thread), into the run stairs. The numbers obtained are to be used on the steel square in laying off the run and rise of each tread and riser on the stringer (see Figure 2-39 ).

• Locate the width of the tread and the height of the riser on the steel framing square.
• Use thee figures to lay off the tread and riser of each step on the stringer equal to the number of risers previously obtained by dividing the story pole into equal spaces. Your stringer is now ready to be cut.