Heatilator ST42A Installation Manual page 30

2. Raised Hearth Extension and Raised Fire-
place
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When creating the platform, allow for the thickness
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Tile, stone or other
non-combustible finishing
material
20 in. minimum
Hearth Extension
1/2 in. Micore
or equivalent
insulation
Figure 7.8 Raised Hearth Extension and Fireplace Framing Materials

Continuous,
non-combustible sealant
Protective Metal
Hearth Strips
Non-combustible
Framing Material
Heatilator • ST42A Installation Manual • 4012-051 • Rev O • 02/22
Note: The bottom of the fireplace
opening is 5 7/8 in. (149 mm)
above the bottom of the
fireplace. Finished hearth must
NOT extend above this level.
Platform must be built
to raise the bottom of
the fireplace opening
to the level of the
desired hearth height.
Floor and platform constructed of
wood or other combustible material