
12
CHIMNEYS AND DRAFT
Chimney Connector Systems and Clearances
from Combustible Walls for Residential
Heating Appliances:
Minimum 3
1
⁄
2
" thick brick masonry all framed into combus
-
tible wall with a minimum of 12" 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.
Solid-insulated, listed factory-built chimney length of the
same inside diameter as the chimney connector and hav-
ing 1" or more of insulation with a minimum 9" air space
between the outer wall of the chimney length and combus-
tibles.
Sheet steel chimney connector, minimum 24 gauge in thick
-
ness, with a ventilated thimble, minimum 24 gauge in thick
-
ness, having two 1" air channels, separated from combus
-
tibles by a minimum of 6" of glass fiber insulation. Opening
shall be covered, and thimble supported with a sheet steel
support, minimum 24 gauge in thickness.
Solid insulated, listed factory-built chimney length with an
inside diameter 2" larger than the chimney connector and
having 1" 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" air space between
the outer wall of chimney section and combustibles. Mini-
mum length of chimney section shall be 12" chimney sec
-
tion spaced 1" away from connector using sheet steel sup
-
port 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 surfaces
of minimum 24 gauge thickness. Fasteners used to secure
chimney section shall not penetrate chimney flue liner.
Figure 11
Figure 12
Figure 13
Figure 14