Mantel And Wall Projections; Finishing The Hearth Extension - Heatilator C40 Installation Manual

C. Mantel and Wall Projections
A combustible mantel may be positioned no lower than 60
in. (1524 mm) from the base of the fi replace.
Refer to Section 3 for reduced mantel height allowances.
The combustible mantel may have a maximum depth of
12 in. (305mm). Combustible trim pieces that project no
more than 3/4 in. (19 mm) from the face of the fi replace
can be placed no closer than 6 in. (152 mm) from the top
or side of the decorative front. Combustible trim must not
cover:
• the metal surfaces of the fi replace
• where the non-combustible board is placed over the
metal surfaces
• the space between the metal face of the fi replace and
framing members
Mantel
Trim
60 in.
(1524 mm)
48 in.
(1219 mm)
Figure 7.2 Mantel Specifi cations
Heatilator • C40 Constitution • 480-2340 Installation Manual • Rev B 01-29-13
Clearances are
from bottom of
appliance to lower
edge of mantel or
trim
D. Finishing the Hearth Extension
WARNING! Risk of Fire!
bers or other burning material falling from the fi replace
may ignite fl ooring or concealed combustible surfaces.
• Protective metal hearth strips MUST be installed.
• Hearth extensions MUST be installed exactly as
specifi ed.
A hearth extension must be installed with all fi replaces to
protect the combustible fl oor in front of the fi replace from
both radiant heat and sparks.
• You MUST use a hearth extension with this fi replace.
• Refer to Figure 7.4 for minimum dimensions.
• This fi replace 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 7.1
to convert a k value to an R value,
• Refer to Table 7.2 for hearth extension insulation
alternatives.
Table 7.1
R = 1/k x inches of thickness
Table 7.2
Hearth Extension Insulation Alternatives, R Value = 2.06
Material
Hearth & Home HX4
USG Micore 300™
USG Durock™ Cement Board
Cement Mortor
Common Brick
Ceramic Tile
Armstrong™ Privacy Guard
Plus
Marble
High temperatures, sparks, em-
Minimum
k per inch r per inch thickness
thick thick required
0.49 2.06
0.49 2.06
1.92 0.52
5.0 0.20 10 1/2in.
5.0 0.20 10 1/2 in.
12.50 0.08 25 3/4 in.
0.460 2.18
29 1/2 in. 41 1/4 in.
14.3-20.0 0.07-0.05
1 in.
1 in.
4 in.
1 in.
35