Clearance Requirements from Vent Terminations to Building Openings
<When supplying combustion air from the outdoors (Direct Vent)>
D
E
L
Ref
A=
Clearance above grade, veranda, porch, deck, or balcony
B=
Clearance to window or door that may be opened
C=
Clearance to permanently closed window
Vertical clearance to ventilated soffit located above the
terminal within a horizontal distance of 2 feet (61 cm)
D=
from the center line of the terminal
E=
Clearance to unventilated soffit
F=
Clearance to outside corner
G=
Clearance to inside corner
Clearance to each side of center line extended above
H=
meter/regulator assembly
I=
Clearance to service regulator vent outlet
Clearance to nonmechanical air supply inlet to building or
J=
the combustion air inlet to any other appliance
Clearance to a mechanical air supply inlet
K=
Clearance above paved sidewalk or paved driveway located
L=
on public property
M=
Clearance under veranda, porch, deck, or balcony
1
In accordance with the current ANSI Z223.1 / NFPA 54 National Fuel Gas Code
* Clearance in accordance with local installation codes and the requirements of the gas supplier.
Clearance to opposite wall is 24 inches (60 cm).
8
B
C
F
B
Description
G
A
H
B
B
B
J
A
B
Vent Terminal
Air Supply Inlet
I
M
K
Area Where Terminal
is Not Permitted
US Direct Vent Installations
12 in (30 cm)
12 in (30 cm)
*
*
*
*
*
*
*
12 in (30 cm)
3 ft (91 cm) above if within
10 ft (3 m) horizontally
*
*
1