52 7/8"
52 7/8"
27"
27"
53 1/8"
53 1/8"
68"
68"
20"
20"
FLOOR
FLOOR
COMBUSTIBLE
COMBUSTIBLE
26 3/8"
26 3/8"
WARNING: THE HEARTH EXTENSION AND THE
WARNING: THE HEARTH EXTENSION AND THE
METAL SAFETY STRIP SHOULD BE INSTALLED
METAL SAFETY STRIP SHOULD BE INSTALLED
ONLY IN A HORIZONTAL RELATIONSHIP TO THE
ONLY IN A HORIZONTAL RELATIONSHIP TO THE
FIREPLACE, AS ILLUSTRATED.
FIREPLACE, AS ILLUSTRATED.
METAL SAFETY STRIP
METAL SAFETY STRIP
HE
AR
TH
PR
OT
EC
TO
R
HEARTH PROTECTOR
METAL
METAL
SAFETY STRIP
SAFETY STRIP
HEARTH EXTENSIONS
HEARTH EXTENSIONS
FLOOR LINE WITH RAISED HEARTH
FLOOR LINE WITH RAISED HEARTH
TOP OF
TOP OF
RAISED HEARTH
RAISED HEARTH
12" (MIN)
12" (MIN)
20"
20"
(MIN)
(MIN)
12" (MIN)
12" (MIN)
F
LOOR
P
ROTECTION
The ability of insulating material to retard the transfer of heat may be expressed as either Thermal Conduc-
tance (C), Thermal Conductivity (K), or Thermal Resistance (R). The mathematical relationship of these
values and the formulas for converting one value to another is as follows:
C=K divided by the material thickness
(Example C = .43 divided by 1/2 (.50)
C = .86)
K = C multiplies by the material thickness
(Example K = .86 multiplied by 1/2 (.50)
K = .43)
R= The material thickness divided by K
(Example R = 1/2 (.50) divided by .43
R = 1.16)
With either type hearth extension minor shifting of the supporting floor or expansion and contraction may
eventually cause a crack to develop between the hearth extension and the face of the fireplace. To help
prevent the crack from developing, the hearth extension materials must be firmly fastened in place. Wall ties
should be screwed to the face of the fireplace and imbedded in the mortar joints of brick, stone, or other non-
combustible materials. The metal safety strip packed with the fireplace must be placed beneath the fireplace
and extended under the hearth extension or into a mortar joint of the hearth extension as shown by Figures 9
and 11. In the event a crack does eventually develop, the metal safety strip will serve as a barrier to prevent
sparks or embers from falling from the fireplace onto combustible flooring materials.
11
F
IGURE
11
53D9035. Rev 1 03/03
Summary of Contents for HWB600
Page 5: ...6 4 CLEARANCES 53D9035 Rev 1 03 03 ...
Page 6: ...CLEARANCES 5 53D9035 Rev 1 03 03 ...
Page 7: ...6 CLEARANCES 53D9035 Rev 1 03 03 ...
Page 13: ...12 FIREPLACE COMPONENTS 53D9035 Rev 1 03 03 ...
Page 37: ...NOTES 36 53D9035 Rev 1 03 03 ...
Page 38: ...NOTES 37 53D9035 Rev 1 03 03 ...
Page 39: ...NOTES 38 53D9035 Rev 1 03 03 ...
Page 52: ...11 53D9036 Rev 1 03 03 FIREPLACE COMPONENTS FIGURE 13 ...