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127051-01_E
6
FIREPLACE INSTALLATION
Continued
MANTELS
A mantel may be installed if desired (see Figures 4 and 5). Woodwork
such as wood trims, mantels or any other combustible material
projecting from front face, must not be placed within 12" of fireplace
opening and within 9" of top louver opening. Combustible materials
above 12" and projecting more than 1 1/2" from fireplace must not
be placed less than 12" from top opening of fireplace (NFPA 211,
Section - Clearance from Combustible Material).
Mantels or any other combustible material may come up to side edge
of black metal face of fireplace if projection from front face falls within
limits shown in Figure 4.
Figure 4 - Mantel Clearances to Combustible Material
Non-Combustible
Materials Below
Top Spacer
DRAIN PAN (DP42)
For outdoor installations, the fireplace enclosure must allow for
adequate drainage and fresh air ventilation. It is recommended that
a sealed, corrosion resistant catch pan with provision for drainage
be installed under the fireplace within the fireplace enclosure (see
Accessories, page 19).
HEARTH EXTENSION
A hearth extension projecting a minimum of 20" in front of and a
minimum of 12" beyond each side of fireplace opening is required
to protect combustible floor construction in front of fireplace. Fab-
ricate a hearth extension using a material which meets the following
specifications: a layer of noncombustible, inorganic material having
a thermal conductivity of k = .84 BTU IN/FT
2
HR °F (or less) at 1"
thick. For example, if material selected has a k factor of 0.25, such
as glass fiber, the following formula would apply:
0.25 x 1.0" = 0.30" thickness required
0.84
Thermal conductivity "k" of materials can be obtained from manu-
facturer or supplier of noncombustible material. If hearth extension
is to be covered, use noncombustible material such as tile, slate,
brick, concrete, metal, glass, marble, stone, etc. Provide a means to
prevent hearth extension from shifting and seal gap between fireplace
frame and hearth extension with a non-combustible material such
as sand-cement grout (see Figure 3).
WARNING: Hearth extension is to be installed
only as shown in Figure 3.
Figure 3 - Hearth Extension
Fireplace Front
Fireplace Front Raised Hearth
Fireplace Front Elevated
Seal Gap
Seal Gap
Ember Protector
Ember Protector
Ember Protector
Hearth
Extension
Hearth Extension, Noncirculating Models
33°
Combustible
Material
Safe Zone for Projection
of Combustible
Materials
Fireplace Opening
Top
Spacer
Upper
Section of
Fireplace
12
1
/
4
"
(312 mm)
Ref.
15"
(381 mm)
Min.
12"
(305 mm)
Min.
6"
(153 mm)
Ref.
1
1
/
2
"
(38 mm)
Max.
3" (77 mm)
Nom.
FIREBOX
SAFE ZONE
Top View of Fireplace
33°
Min. 12" from
Perpendicular Side Wall
3"
(77 mm)
2" (51 mm)
Max.
8"
(204
mm)
