20
31072 Rev G
08/04
MHC36 AND MHR36 INSTALLATION INSTRUCTIONS
Figure 19 - Factory Built Hearth Extension
Figure 20 - Field Constructed Hearth Extension
WARNING!
Hearth extensions are to be installed only as illustrated to prevent high temperatures from occurring
on concealed combustible materials. Hearth sealing strips prevent burning or hot particles from inad-
vertently falling directly on combustible surfaces in the event the building should settle and disturb
the original construction.
14. Hearth Extension
A hearth extension must be installed with all fireplaces to protect the combustible floor in front of the fireplace from
both radiant heat and sparks.
The construction of, and materials used for a hearth extension are shown in Figures 19 and 20. A hearth extension
of this construction may be covered with any noncombustible decorative material and may have a maximum thickness
as per the illustration. Seal gaps between the hearth extension and the front of the fireplace with a bead of
noncombustible sealant.
Field constructed hearth extensions should be constructed in accordance with the instructions in Figure 20. The field
constructed hearth extension must be constructed from 1/2 in. MICORE CV230, or a material with an equivalent
insulation value.
