12
Check 1—Proper Chimney Termination
A masonry chimney used as a vent for gas-fired equipment must
extend at least 3 ft (91.4 cm) above the highest point where it
passes through the roof. It must extend at least 2 ft (61 cm)
higher than any portion of a building within a horizontal distance
of 10 ft (3 m). In addition, the chimney must terminate at least 3 ft
(91.4 cm) above any forced air inlet located within 10 ft (3 m). The
chimney must extend at least 5 ft (1.5 m) above the highest
connected equipment draft hood outlet or flue collar.
If the chimney does not meet these termination requirements, but
all other requirements in the checklist can be met, it may be
possible for a mason to extend the chimney. If this will not be
practical, see “Fix 1—Liner Termination.”
Termination 10 ft (3 m) or Less From Ridge, Wall or Parapet
Termination More Than 10 ft (3 m) From Ridge, Wall or
Parapet
No
Yes
No
Yes
Proper chimney
termination?
(Check 1)
Line, terminate with
listed vent cap
(Fix 1)
Chimney channel
free of solid and
liquid fuel
appliances?
(Check 2)
Change venting
arrangements
(Fix 2)
No
No
No
No
Yes
Yes
Yes
Yes
Rebuild crown
(Fix 3)
and/or reline
(Fix 4)
Reline
(Fix 4)
Reline
(Fix 4)
Reline
(Fix 4)
Crown in good
condition?
(Check 3)
Cleanout free of
debris?
(Check 4)
Liner in good
condition?
(Check 5)
Dilution air
available?
(Check 6)
Complete the
installation.
(Check 7)
A. 10 ft (3 m) or less
B. 2 ft (61 cm) minimum
C. 3 ft (91.4 cm) minimum
D. Wall or parapet
E. Chimney(s)
A. More than 10 ft (3 m)
B. No height above parapet
required when distance from
walls or parapet is more than
10 ft (3 m).
C. 3 ft (91.4 cm) minimum
D. Chimney
E. Wall or parapet
F. Height above any roof surface
within 10 ft (3 m) horizontally
G. 10 ft (3 m)
H. 2 ft (61 cm) minimum
I. Ridge
B
A
B
C
D
E
A
B
C
E
F
A
D
F
I
C
D
B
E
A
C
G
H