9
Vent Terminal
Clearance
A=
Above grade, veranda, porch, deck,
or balcony
B=
Window or door that may be opened
C=
Permanently closed window
D=
Vertical clearance to ventilated soffit
located above the terminal within a
horizontal distance of 2 feet from the
center of the terminal
*
E=
Unventilated soffit
*
F=
Outside corner
*
G=
Inside corner
*
H=
Each side of center line extended
above meter/regulator assembly
3' (0.9m) within a height 15' (4.5m)
above meter/regulator assembly
I=
Service regulator vent outlet
3' (0.9m)
J=
Nonmechanical air supply inlet or
combustion air inlet to any other
appliance
K=
Mechanical air supply inlet
3' above if within
10' [6' (1.8m)]
L=
Above paved sidewalk or paved
driveway located on public property
Under veranda, porch, deck, or
balcony
* [7' (2.1m***)]
M=
[ ] = indicates clearances required in Canada
*Maintain clearances in accordance with local installation codes and the requirements of the gas supplier
***A vent shall not terminate directly above a sidewalk or paved driveway that is located between two
single family dwellings and serves both dwellings.
****Permitted only if veranda,porch,deck,or balcony is fully open on a minimum of two sides beneath the floor.
* [12" (300mm)****]
*
12" [12" (300mm)]
4’ (1.2m) below or to the side of
opening, or 1’ (0.3m)above opening
[36" (900mm)]
Air Supply Inlet
Area Where Terminal
is Not Permitted
Indoor Combustion Air
*
*
*
*
3' (0.9m) within a height 15' (4.5m)
above meter/regulator assembly
3' (0.9m)
3' above if within
10' [6' (1.8m)]
* [7' (2.1m***)]
* [12" (300mm)****]
*
12" [12" (300mm)]
12" [36" (900mm)]
4’ below or to the side of
opening, or 1’ above opening
[36" (900mm)]
12" [36" (900mm)]
Outdoor Combustion Air
(Direct Vent)
Clearance Requirements from Vent Terminations to Building Openings
* All clearance requirements are in accordance with ANSI Z21.10.3 and the National Fuel Gas Code,
ANSI Z223.1 and in Canada, in accordance with NSCNGPIC.
