Design Manual

11 R-TRWH-E-02 Rev D
Ref
Description
Canadian Installations US Installations
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
36 inches (91 cm) 12 inches (30 cm)
C Clearance to permanently closed window * *
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
* *
E Clearance to unventilated soffit * *
F Clearance to outside corner * *
G Clearance to inside corner * *
H
Clearance to each side of center line
extended above meter/regulator assembly
3 feet (91 cm) within a
height 15 feet (4.5 m)
above the meter/
regulator assembly
*
I Clearance to service regulator vent outlet 36 inches (91 cm) *
J
Clearance to nonmechanical air supply
inlet to building or the combustion air inlet
to any other appliance
36 inches (91 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 (3 m)
horizontally
L
Clearance above paved sidewalk or
paved driveway located on public property
7 feet (2.13 m) 1 *
M
Clearance under veranda, porch, deck, or
balcony
12 inches (30 cm) 2 *
NOTE: An outdoor water heater with integral vent and intake is functionally similar to a direct vent
product in that the combustion air is drawn from the outside and the flue products are vented to the
outside. These clearances apply to indoor and outdoor water heaters.
1 A vent shall not terminate directly above a sidewalk or paved driveway that is located between two
single family dwellings and serves both dwellings.
2 Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath
the floor.
∗ For clearances not specified in ANSI Z223.1/NFPA 54 or CSA B149.1, clearances are in
accordance with local installation codes and the requirements of the gas supplier.
Vent Termination Clearances