Civil Engineering Reference
In-Depth Information
Figure G12-10
Ski chalet and garage
for Design Example 3.
the chalet has a cold, ventilated roof (roof insulation between the heated
space and the ventilated space more than 25 °F h ft
2
/Btu).
Balanced Loads
Both the chalet and garage are in Terrain Category B, so their exposure factor,
C
e
, is 1.2 from Table 7-2. Since the chalet has a cold, ventilated roof, its
C
t
is
1.1 from Table 7-3, whereas the unheated garage's thermal factor is 1.2. Since
the chalet's roof slope is 4 on 12, the surface is slippery, and there is nothing
to prevent snow sliding off the eaves, its slope factor,
C
s
, is 0.86 from Figure
7-2b or from the equations in Commentary Section C7.4. Similarly, the garage
has a 4-on-12 slope and an unobstructed, slippery surface. However, its
C
t
is
1.2, so
C
s
is 0.94 from Figure 7-2c or the equations in the Commentary. Both
the chalet and garage are of ordinary importance, hence
I
s
is 1.0.
