89Installing a Common Vent System
Indirect Venting
Ref Description
Canadian Non-Direct
Vent Installations
1
US Non-Direct Vent
Installations
2
A
Clearance above grade, veranda, porch, deck, or
balcony
12 in (30 cm) 12 in (30 cm)
B Clearance to window or door that may be opened 36 in (91 cm)
48 in (120 cm) below or
to side of opening; 12 in
(30 cm) above opening
C Clearance to permanently closed window 12 in (30 cm)* 12 in (30 cm)*
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
3 ft (91 cm)* 3 ft (91 cm)*
E Clearance to unventilated soffit 3 ft (91 cm)* 3 ft (91 cm)*
F Clearance to outside corner 2 ft (61 cm)* 2 ft (61 cm)*
G Clearance to inside corner 12 in (30 cm)* 12 in (30 cm)*
H
Clearance to each side of center line extended above
meter/regulator assembly
36 in (91 cm) within a
height 15 ft (4.57 m)
above the meter/
regulator assembly
3 ft (91 cm) within a
height of 15 ft (4.6 m)*
I Clearance to service regulator vent outlet 36 in (91 cm) 3 ft (91 cm)*
J
Clearance to non-mechanical air supply inlet to
building or the combustion air inlet to any other
appliance
36 in (91 cm)
48 in (120 cm) below or
to side of opening; 12 in
(30 cm) above opening
K Clearance to a mechanical air supply inlet 6 ft (1.83 m)
36 in (91 cm) above
if within 10 ft (3 m)
horizontally
L
Clearance above paved sidewalk or paved driveway
located on public property
7 ft (2.13 m)
†
7 ft (2.13 m)
†
M
Clearance under veranda, porch deck, or balcony
12 in (30 cm)
‡
12 in (30 cm) - open on
3 sides*
1 In accordance with the current CSA B149.1 Natural Gas and Propane Installation Code
2 In accordance with the current ANSI Z223.1/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 veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
* Suggested minimum clearances by the manufacturer. If the clearances required by the local authority or gas supplier are
different from those from the table above, the greater clearance should apply.
To Next Page
Loading...
Need help?
General
