HORIZONTAL VENTING REQUIREMENTS
MINIMUM VERTICAL RISE* FROM TOP OF UNIT: 18 IN. (to top of 7” pipe)
MINIMUM HORIZONTAL RUN: 6 IN.
MAXIMUM HORIZONTAL RUN: 20 FT. (Horizontal runs must maintain 1/4” rise per ft.)
TOTAL HORIZONTAL & VERTICAL RUN MUST NOT EXCEED 32 FT.
*Minimum vertical rise directly off the top of the unit is determined by the length of the horizontal run. Refer to the vent-
ing diagram on page #9.
ELBOWS:
For each additional elbow used after the first elbow, you must subtract 5 ft. from the maximum horizontal
run allowed.
For example: A vertical rise of 18” directly off the top of the unit with a 90
o
elbow would be allowed to run
6‟ with 1/4” rise per ft.. If an additional elbow is used within this vent run, the maximum horizontal run
allowed would be 1‟ with 1/4” rise per ft.. (6 ft - 5 ft. (for additional elbow) = 1 ft.)
VERTICAL VENTING REQUIREMENTS
NOTE:
MINIMUM VERTICAL RISE FROM TOP OF UNIT: 18 IN. (to top of 7” pipe)
MAXIMUM VERTICAL RISE FROM TOP OF UNIT: 32 FT.
ELBOWS: 45
o
only (Dura-Vent chimney systems)
MINIMUM CLEARANCE TO COMBUSTIBLES: 1"
WHEN VERTICALLY TERMINATING, THE MINIMUM CHIMNEY HEIGHT ABOVE THE ROOFLINE IS DETERMINED BY THE
FOLLOWING CHART:
Roof Pitch
Minimum Chimney Height
Roof Pitch
Minimum Chimney Height
Flat to 6/12
1 ft.
13/12 to 16/12
6 ft.
6/12 to 9/12
2 ft.
17/12 to 21/12
8 ft
10/12 to 12/12
4 ft.
Figure 9
Page 12
