Here are four methods of combustible wall chimney connector pass-throughs. This information
was provided from NFPA 211.
METHOD A.
12" (304.8 mm) Clearance to Combustible Wall Member: Using a
minimum thickness 3.5" (89 mm) brick and a 5/8" (15.9 mm) mini-
mum wall thickness clay liner, construct a wall pass-through. The clay
liner must conform to ASTM C315 (Standard Specifi cation for Clay
Fire Linings) or its equivalent. Keep a minimum of 12" (304.8 mm)
of brick masonry between the clay liner and wall combustibles. The
clay liner shall run from the brick masonry outer surface to the inner
surface of the chimney fl ue liner but not past the inner surface. Firmly
grout or cement the clay liner in place to the chimney fl ue liner.
METHOD B.
9" (228.6 mm) Clearance to Combustible Wall Member: Using a 6"
(152.4 mm) inside diameter, listed, factory-built Solid-Pak chimney
section with insulation of 1" (25.4 mm) or more, build a wall pass-
through with a minimum 9" (228.6 mm) air space between the outer
wall of the chimney length and wall combustibles. Use sheet metal
supports fastened securely to wall surfaces on all sides, to maintain
the 9" (228.6 mm) air space. When fastening supports to chimney
length, do not penetrate the chimney liner (the inside wall of the Sol-
id-Pak chimney). The inner end of the Solid-Pak chimney section shall
be fl ush with the inside of the masonry chimney fl ue, and sealed with
a non-water soluble refractory cement. Use this cement to also seal
to the brick masonry penetration.
METHOD C.
6" (152.4 mm) Clearance to Combustible Wall Member: Starting with
a minimum 24 gage (.024" [.61 mm]) 6" (152.4 mm) metal chimney
connector, and a minimum 24 gage ventilated wall thimble which has
two air channels of 1" (25.4 mm) each, construct a wall pass-through.
There shall be a minimum 6" (152.4) mm separation area containing
fi berglass insulation, from the outer surface of the wall thimble to wall
combustibles. Support the wall thimble, and cover its opening with
a 24- gage minimum sheet metal support. Maintain the 6" (152.4
mm) space. There should also be a support sized to fi t and hold the
metal chimney connector. See that the supports are fastened securely
to wall surfaces on all sides. Make sure fasteners used to secure the
metal chimney connector do not penetrate chimney fl ue liner.
METHOD D.
2" (50.8 mm) Clearance to Combustible Wall Member: Start with a
solid-pak listed factory built chimney section at least 12" (304 mm)
long, with insulation of 1" (25.4 mm) or more, and an inside diameter
of 8" (2 inches [51 mm] larger than the 6" [152.4 mm] chimney con-
nector). Use this as a pass-through for a minimum 24-gage single
wall steel chimney connector. Keep solid-pak section concentric with
and spaced 1" (25.4 mm) off the chimney connector by way of sheet
metal support plates at both ends of chimney section. Cover open-
ing with and support chimney section on both sides with 24 gage
minimum sheet metal supports. See that the supports are fastened
securely to wall surfaces on all sides. Make sure fasteners used to se-
cure chimney fl ue liner.
NOTES:
1. Connectors to a masonry chimney, excepting method B, shall extend in one continuous section through the wall pass-through
system and the chimney wall, to but not past the inner fl ue liner face.
2. A chimney connector shall not pass through an attic or roof space, closet or similar concealed space, or a fl oor, or ceiling.
8
A
Minimum chimney clearance to brick
and combustibles 2" (50.8mm)
Masonry
chimney
Minimum 12" (304.8mm)
to combustibles
B
Minimum chimney clearance from
masonry to sheet steel supports
and combustibles 2" (50.8mm)
Nonsoluble refractory cement
Chimney length fl ush
with inside of fl ue
Factory-built
chimney length
Min. air space
9" (228.6mm)
Masonry
chimney
Sheet steel supports
C
Minimum chimney clearance
to sheet steel supports and
combustibles 2" (50.8mm)
Two ventilated air channels
each 1" (25.4mm). Con-
struction of sheet steel.
Masonry
chimney
Sheet steel supports
D
Minimum chimney clearance
to sheet steel supports and
combustibles 2" (50.8mm)
Sheet steel supports
Air space 2"
(50.8mm)
Chimney
section
Masonry
chimney
Minimum clearance
12" (304.8mm)
of brick
Chimney
connector
Fire clay liner
Minimum clearance
9" (228.6mm)
Chimney
connector
Use chimney
mfrs. parts to
attach connector
securely
Solid-insulated
listed factory-built
chimney length
Two air channels each
1" (25.4mm)
Chimney
connector
Minimum 6"
(152.4mm) glass
fi ber insulation
Minimum clearance
2" (50.8mm)
1" (25.4mm)
air space to
chimney length
Chimney
connector
Chimney length
Sheet steel supports