50
Initial Installation
QUALIFIED INSTALLERS ONLY
Table 7: Minimum ‘H’ for Figure 69.
Roof Pitch
Minimum Height (H)
Feet
Meters
Flat to 7/12
1
0.3
Over 7/12 to 8/12
1.5
0.46
Over 8/12 to 9/12
2
0.61
Over 9/12 to 10/12
2.5
0.76
Over 10/12 to 11/12
3.25
0.99
Over 11/12 to 12/12
4
1.22
Over 12/12 to 14/12
5
1.52
Over 14/12 to 16/12
6
1.83
Over 16/12 to 18/12
7
2.13
Over 18/12 to 20/12
7.5
2.29
Over 20/12 to 21/12
8
2.44
Figure 74: Height of Vertical Termination;
Reference Table 7
Figure 76: Use of Wall Straps.
Figure 75: Multi-Story Vent Pipe Installation
NOTES:
1. If an
offset is necessary in the attic to avoid obstructions, it is important to support the vent pipe
every 3’ (914 mm) using wall straps to avoid excessive stress on the elbows.
2. Use 45
°
degree elbows instead of 90
°
degree elbows when ever possible. The 45
°
degree elbow
offers less restriction to the flow of flue gases and intake air.
