RPD-I-S Rev A
9
Venting continued-
Canadian
Installations
1
US
Installations
2
A=
Clearance above grade, veranda, porch, deck or balcony
12 inches
(30 cm)
12 inches
(30 cm)
B=
Clearance to window or door that may be opened
12 inches
(30 cm)
12 inches
(30 cm)
C=
Clearance to permanently closed window
*b
*b
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
*b *b
E=
Clearance to unventilated soffit
*b
*b
F=
Clearance to outside corner
*b
*b
G=
Clearance to inside corner
*b
*b
H=
Clearance to each side of center line extended above meter/regulator
assembly
3 feet (91 cm)
within a height 15
feet (4.6 m) above
the
meter/regulator
assembly
*b
I=
Clearance to service regulator vent outlet or oil tank vent
36 inches
(91 cm)
*b
J=
Clearance to non-mechanical air supply inlet to building or the
combustion air inlet to any other appliance
12 inches
(30 cm)
12 inches
(30 cm)
K=
Clearance to a mechanical air supply inlet
6 feet
(1.83 m)
3 feet
(91 cm)
above if
within 10
feet
horizontally
L=
Clearance above paved sidewalk or paved driveway located on public
property
7 feet
(2.13 m)†
7 feet
(2.13 m)†
M=
Clearance under a veranda, porch, deck, or balcony
12 inches
(30 cm) ‡
*b
1
In accordance with the current CAN/CGA-B149
Installation Codes
.
2
In accordance with the current ANSI Z223.1-(Latest edition)/NFPA 54
National Fuel Gas Code
.
† 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 a veranda, porch, deck or balcony is fully open on a minimum of two sides beneath the
floor.
*a) A minimum clearance value determined by testing in accordance with section 2.20.
*b) “Clearance in accordance with local installation codes and the requirements of the gas supplier”.
The vent system must terminate so that proper clearances are maintained as cited
in local codes or the latest edition of the National Fuel Gas Code, ANSI
Z223.1.73.4e and 7.8a, b as follows:
1. Do not terminate near soffit vents or crawl space or other area where condensate or
vapor could create a nuisance or hazard or cause property damage.
2. Do not terminate the exhaust vent terminal where condensate or vapor could cause
damage or could be detrimental to the operation of regulators, relief valves, or other
equipment.
3. Do not terminate the exhaust vent terminal over public area or walkways where
condensate or vapor can cause nuisance or hazard.
4. The vent shall terminate a minimum of 12”
(25.4 cm)
above expected snowfall level
to prevent blockage of vent termination.
