New Buck Corporation 94NC - Manual (Page 16)

Page 14
a) Minimum 3.5-in thick brick masonry all framed into
combustible wall with a minimum of 12-in brick
separation from clay liner to combustibles. The
fireclay liner shall run from outer surface of brick wall
to, but not beyond , the inner surface of chimney flue
liner and shall be firmly cemented in place.
b) Solid-insulated factory-built chimney length of the
same inside diameter as chimney connector and
having 1-in. or more of insulation with a minimum 9-in.
air space between outer wall of chimney length and
combustibles.
c) Sheet steel chimney connector, minimum 24 gauge in
thickness, with a ventilated thimble, minimum 24
gauge in thickness, having two 1-in. air channels,
separated from combustibles. by a minimum of 6-in. of
fiber insulation. Opening shall be covered, and thimble
supported with a sheet steel support, minimum 24
gauge in thickness.
d) Solid insulated, listed factory-built chimney length with
an inside diameter 2-in. larger than chimney
connector and having 1-in. or more of insulation,
serving as a pass-through for a single wall sheet steel
chimney connector of minimum 24 gauge thickness,
with a minimum 2-in. air space between outer wall of
chimney section and combustibles. Minimum length of
chimney section shall be 12-in. chimney section
spaced 1-in. away from connector using sheet steel
support plates on both ends of chimney section.
Opening shall be covered, and chimney section
supported on both sides with sheet steel supports
securely fastened to wall surface of minimum 24
gauge thickness. Fasteners used to secure chimney
section shall not penetrate chimney flue liner.
Installing a thimble through combustible wall
Chimney Connector Systems and Clearances from Combustible Walls for Residential Heating Appliances