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Finishing
• Materials which will not ignite and burn, composed of
any combination of the following:
- Steel
- Iron
- Brick
- Tile
- Concrete
- Slate
- Glass
- Plasters
• Materials reported as passing
ASTM E 136, Standard
Test Method for Behavior of Metals, in a Vertical Tube
Furnace at 750° C
• Materials made of or surfaced with any of the following
materials:
- Wood
- Compressed paper
- Plant fibers - Plastic
• Any material that can ignite and burn; flame proofed or
not, plastered or un-plastered
Table 10.1
R = 1/k x inches of thickness
Table 10.2
WARNING! Risk of fire!
High temperatures, sparks,
embers or other burning material falling from the fireplace
may ignite flooring or concealed combustible surfaces.
• Protective metal hearth strips MUST be installed.
• Hearth extensions MUST be installed exactly as
specified.
• You MUST use a hearth extension with this fireplace.
• Refer to Figure 10.1 for minimum dimensions.
• This fireplace has been tested and approved for use with
a hearth extension insulated to a minimum R value of
2.06.
• The hearth extension material MUST be covered with
tile, stone or other non-combustible material.
• Manufactured hearth materials will usually have a
published
R value
(resistance to heat) or
k value
(conductivity of heat). Refer to the formula in Table 10.1
to convert a k value to an R value,
• Refer to Table 10.2 for hearth extension insulation
alternatives.
B
8 in. (203mm)
from each side of
fuel loading door
A
Figure 10.1 Hearth Extension Dimension
A. Non-Combustible Materials
B. Combustible Materials
C. Hearth Extension
Hearth Extension Insulation Alternatives, R Value = 2.06
Material
k per inch
thick
r per inch
thick
Minimum
thickness
required
Hearth & Home HX4
0.49
2.06
1 in.
USG Micore 300™
0.49
2.06
1 in.
USG Durock™ Cement
Board
1.92
0.52
4 in.
Cement Mortor
5.0
0.20
10 1/2in.
Common Brick
5.0
0.20
10 1/2 in.
Ceramic Tile
12.50
0.08
25 3/4 in.
Armstrong™ Privacy Guard
Plus
0.46
2.18
1 in.
Marble
14.3-20.0 0.07-0.05
29 1/2 in. 41 1/4 in.
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.
Model # 7100FP
A
B
in.
41
20
mm
1041
508