305, 505, 705 Indoor Manual
25
Flue Terminal Clearances (
ANS Z21.10.3
●
CSA 4.3)
INSIDE
CORNER DETAIL
FIXED
CLOSED
OPERABLE
FIXED
CLOSED
OPERABLE
B
B
B
A
J
B
M
C
F
B
B
E
D
L
G
A
H
K
I
1
A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves
both dwellings.
2
Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
∗
For clearances not specified in
ANSI Z223.1/NFPA 54
or
CSA B149.1
, clearances are in accordance with local installation codes and the
requirements of the gas supplier.
X
V
AIR SUPPLY INLET
VENT TERMINAL
AREA WHERE
TERMINAL IS NOT
PERMITTTED
Ref
Description US
Installations
A
Clearance above grade, veranda, porch, deck, or balcony
12 inches (30 cm)
B
Clearance to window or door that may be opened
12 inches (30 cm)
C
Clearance to permanently closed window
*
D
Vertical clearance to ventilated soffit, located above the terminal
within a horizontal distance of 2 feet (61 cm) from the center line
of the terminal
*
E
Clearance to unventilated soffit
*
F
Clearance to outside corner
*
G
Clearance to inside corner
*
H
Clearance to each side of center line extended above meter/
regulator assembly
*
I
Clearance to service regulator vent outlet
*
J
Clearance to nonmechanical air supply inlet to building or the
combustion air inlet to any other appliance
12 inches (30 cm)
K
Clearance to a mechanical air supply inlet
3 feet (91 cm) above if within
10 feet (3 m) horizontally
L
Clearance above paved sidewalk or paved driveway located on
public property
*
M
Clearance under veranda, porch, deck, or balcony
*
