32
VENTING INFORMATION
Table 13. Vent Termination Clearances
Clearance Location
CANADIAN INSTALLATIONS
a
US INSTALLATIONS
b
Direct Vent (2-pipe) &
Conventional Vent (1-pipe) Furnaces
Direct Vent
(2-pipe) Furnaces
Conventional Vent
(1-pipe) Furnaces
A
Clearance above grade, veranda, porch, deck,
balcony, or maximum expected snow level.
12 inches (30cm)
12 inches (30cm)
12 inches (30cm)
B
Clearance to window or door that may be
opened.
6 inches (15cm) for appliances
< 10,000 Btuh (3kW)
6 inches (15cm) for appliances
< 10,000 Btuh (3kW)
4 ft. (1.2m) below or to side of
opening; 1 ft. (300mm) above
opening
12 inches (30cm) for appliances
10,000 Btuh - 100,000 Btuh (30kW)
9 inches (23cm) for appliances
10,000 Btuh - 50,000 Btuh (30kW)
36 inches (91cm) for appliances
> 100,000 Btuh (30Kw)
12 inches (30cm) for appliances
> 50,000 Btuh (30Kw)
C
Clearance to permanently closed window
12 inches (30cm) suggested or as needed to avoid
condensation on glass.
12 inches (30cm) suggested or as needed to avoid condensation on glass.
D
Vertical clearance to ventilated soffit located
above the terminal within a horizontal distance of
2 feet (61cm) from the center line of the terminal.
Clearance must be greater than the depth of
the soffit unless it complies with Figure 20
(page 33)
Clearance must be greater than the depth of the soffit unless
it complies with Figure 20 (page 33)
E
Clearance to unventilated soffit.
Clearance must be greater than the depth of the
soffit unless it complies with Figure 20 (page 33)
Clearance must be greater than the depth of the soffit unless
it complies with Figure 20 (page 33)
F
Clearance to outside corner.
All Clearances in this Figure apply
on both walls
All Clearances in this Figure apply on both walls
G
Clearance to inside corner.
All Clearances in this Figure apply
on both walls
All Clearances in this Figure apply on both walls
H
Clearance to each side of center line extended
above meter/regulator assembly.
3 feet (91cm) within a height 15 feet
above the meter/regulator assembly
3 feet (91cm) within a height of 15 feet
I
Clearance to service regulator vent outlet.
3 feet (91cm)
3 feet (91cm) in any direction
J
Clearance to non-mechanical air supply inlet to
building or the combustion air inlet to any other
appliance.
6 inches (15cm) for appliances
< 10,000 Btuh (3kW)
6 inches (15cm) for appliances
< 10,000 Btuh (3kW)
4 ft. (1.2m) below or to side of
opening; 1 ft. (300mm) above
opening
12 inches (30cm) for appliances
10,000 Btuh - 100,000 Btuh (30kW)
9 inches (23cm) for appliances
10,000 Btuh - 50,000 Btuh (30kW)
36 inches (91cm) for appliances
> 100,000 Btuh (30Kw)
12 inches (30cm) for appliances
> 50,000 Btuh (30Kw)
K
Clearance to mechanical air supply inlet.
6 feet (1.83m)
3 feet (91cm) above if within
10 feet (3m) horizontally
3 ft. (91cm) above if within
10 feet (3m) horizontally
L
Clearance above paved sidewalk or driveway
located on public property.
7 feet (2.13m)
c
7 feet (2.13m)
c
7 ft. (2.13m)
M
Clearance under open veranda, porch, deck,
or balcony.
12 inches (30cm)
d
12 inches (30cm)
d
12 inches (30cm)
d
NOTES:
a =
In accordance with the current CSA B149.1 Natural Gas and Propane Installation Guide Code
b =
In accordance with the current ANSI Z223.1 / NFPA 54 Natural Fuel Gas Code
c =
A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.
d =
Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
VENT TERMINAL
AIR SUPPLY INLET
AREA WHERE TERMINAL IS NOT PERMITTED
