D. frame the fireplace, C. sidewalls/surrounds – Hearth and Home Technologies BIR42-B User Manual
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20
D. Frame the Fireplace
Figure 6.4 shows typical framing using combustible materials (2x4 lumber shown).
• Observe all required air space clearances to combustible materials as shown in Figure 6.2.
18 1/2 in.
[470 mm]
19 3/4 in.
[500 mm]
4 in.
[102 mm]
50° angle
39° angle
24 in.
[610 mm]
BRICK
FRONT
FLUSH
FRONT
24 in.
[610 mm]
22 3/8 in.
[568 mm]
52-7/8 in.
(1343 mm)
42 in.
[1067 mm]
Note: Grid depicts 1 inch squares.
Figure 6.3 Mantel Leg, Surround or Wall Projection (acceptable on both sides of opening)
Figure 6.4 Framing the Fireplace
C. Sidewalls/Surrounds
• Locate adjacent combustible sidewalls a minimum of 24 in. (610 mm) from fireplace opening.
• Mantle leg, surround, stub wall, whether combustible or non-combustible, may be constructed as shown in Figure 6.3.
B
C
A
2 in. (51 mm)
min. air space
clearance
from chimney.
Header MUST NOT be notched!
D
D = extra space needed for outside air connection.
If outside air duct has no bend, this dimension may be
reduced as long as minimum clearances are met.
D
A
B *
C **
D
in.
mm
305
28 3/8
74 1/2
1892
721
1368
12
Model #
* If interior of chase will be drywalled, add the thickness to this meaurement.
** Adjust header height for raised floor under fireplace.
Bir 42-B
The fireplace header cannot be positioned until
after the fireplace assembly is in place.
Framing must be extended straight up, all
the way to the ceiling.
53 7/8
Heatilator • Birmingham BIR42-B • 4059-681C • 9/12