
Heat & Glo • RH-36/RH-42 • 4044-153 Rev U • 11/07
30
Raised Hearth Extension Construction
A raised hearth extension that is
fl
ush with the
fi
replace
opening (Figure 8.6) or less than 4 in. (102 mm) below the
fi
replace opening (Figures 8.4 & 8.5) requires the
fi
replace
to be installed on a non-combustible surface.
IMPORTANT!
Hearth extension design must be determined
before installation of
fi
replace.
Floor
Noncombustible
Framing Material
Noncombustible
Finishing Material
Metal
Hearth Strips
HX3 or HX4
Non-combustible
Material
Figure 8.6 Raised Hearth Extension Detail
HX3 or HX4
Figure 8. 7 Non-combustible Surface for Hearth Extension
Raised Hearth Extension Framing
The hearth framing must be constructed of non-combustible
materials (Figure 8) and placed on an HX3 or HX4, or equiv-
alent material (Figure 7). When creating the platform, allow
for the thickness of the non-combustible
fi
nishing materials
(Figure 9).
Noncombustible
Framing Material
HX3, HX4 or
equivalent
Figure 8. 8 Framing Materials
Noncombustible
Finishing Materials
Figure 8. 9 Finishing Materials