Heatilator BIR42-B Owner's Manual page 42

Raised Hearth Extension Framing
The hearth framing must be constructed of non-combus-
tible materials (Figure 12.2) and placed on 1/2 in. Durock
and 1 in. Micore (or equivalent material) (Figure 12.4).
When creating the platform, allow for the thickness of the
non-combustible finishing materials (Figure 12.5).
IMPORTANT! Hearth extension design must be determined
before installation of fireplace.
Continuous,
non-combustible sealant
Durock
Tile, stone or other
non-combustible material
1 in. Micore or
equivalent insulation
(see Table)
Floor constructed of wood or
other combustible material
Figure 12.2 Hearth Extension Construction
Note: The bottom of the
fireplace opening is 3-3/4 in.
(95.3mm) above the bottom of
the fireplace. Finished hearth
must NOT extend above this
level.
20 in. Min.
Hearth Extension
Non-combustible
Finishing Material
1 in. Micore or
equivalent insulation
& 1/2 in. Durock
Figure 12.3 Raised Platform Hearth Extension Detail
42
Protective
Metal Hearth
Strip
*
*
* 2 in. (51 mm)
Bottom of
fireplace opening
Platform must be built
to raise the bottom of
the fireplace opening
to the level of the
desired hearth height.
Protective Metal
Floor
Hearth Strips
Non-combustible
Framing Material
Heatilator • Birmingham BIR42-B • 4059-681 • 11/11
Non-combustible
Framing Material
Figure 12.4 Raised Platform Hearth Extension-Framing Materials
Non-combustible
Finishing Materials
Figure 12.5 Raised Platform Hearth Extension-Finishing Materials
1 in. Micore or
equivalent insulation
& 1/2 in. Durock