Figure 11a – Vent Terminal Clearances (Other than Direct Vent or Powered Direct Vent Installations)
Clearance above
grade, veranda,
A=
porch, deck or
balcony
Clearance to
window or door
B=
that may be
opened
Clearance to
C=
permanently
closed window
Vertical clearance
to ventilated soffit
located above the
terminal within a
D=
horizontal distance
of 2 feet (61 cm)
from the center line
of the terminal
Clearance to
E=
unventilated soffit
Clearance to
F=
outside corner
Clearance to inside
G=
corner
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".