Figure 46 shows a set of
stairs forming a right triangle. Only one-half the
stairs
are shown. The Pythagorean theorem (Rise^2 +
run^2 = Stringer Length^2) is used to calculate the hypotenuses or
the lengths of the stringers. The top step in figure 46 is attached to
the floor frame. To determine the length of the stringer, use
the
desired
unit rise of 175 mm and unit run of 250 mm. The
stairs have 12 risers and 12
treads. The rise
used in the
Pythagorean theorem to calculate the stringer length will be 175 mm
times 12 = 2100 mm (the true total rise). The run used is 250 mm times
12 = 3000 mm. The square root of 2100 mm
squared plus 3000 mm squared = 3662 mm. 3662 mm is
the
length of the
stringer.
Figure
46 The Top Step Is Attached To The Floor Frame
