Vermont Castings BC36MH Installation & Operating Manual page 15

Minimum Wall Clearances
WITH
Noncombustible
Surround Facing
4" Brick
(Example material)
E
F**
A - Min. clearance
C**
to combustible
perpendicular wall
Side
B - Min. clearance
Wall
to combustible
perpendicular wall when
using noncombustible wall shield*
Combustible material permitted within shaded area.
* Noncombustible wall shield requires 1" MHSC
EH2416 insulation (minimum R Value = 1.85) between
decorative noncombustible rigid covering and combustible wall.
Minimum height and width is 40" x 40".
** Dimension/degree of angle will vary depending on thickness
of noncombustible surround facing.
A
BC36MH 16"
(406 mm) (305 mm)
BC42MH 20"
(508 mm) (305 mm)
Fig. 22 Combustible side wall protection and hearth extension dimensions.
Example of Determining Hearth
Extension Equivalents
To determine the thickness required for any new mate-
rial:
NEW K of new material (per inch)
required =
thickness K of listed material (per inch)
Example of Common Brick
T (new) = 5.0 / 0.458 x 0.50 in. = 5.46 in. (new required
thickness).
7412972
WITHOUT
Noncombustible
Surround Facing
Shaded area starts
1/2" away from
edge of unit.
Firebox
E
Opening
Side
Wall
B C
12" 48° 41°
12" 42° 35°
thickness
X of listed
material
BC36MH, BC42MH Woodburning Fireplace
Minimum Hearth Extension Dimensions
(for On-Site Construction)
4"
D
May install
noncombustible
decorative
covering
OR .018" min.
sheet metal
4" Min.
Combustible
Floor
D E F
18" 14"
(457 mm) (356 mm) (229 mm) (406 mm) (1372 mm)
18" 14"
(457 mm) (356 mm) (305 mm) (508 mm) (1676 mm)
FP594MH
BC36MH
combustible min.
6/2/99 djt
COMMON MATERIALS AND FACTORS
MATERIAL
EH2416
(MHSC)
Common Brick
R Value is for one (1) inch.
* Units of K = BTU/SQ FT/HR/?F/IN
** Thickness of Listed Material
Fig. 23 Hearth extension material factors.
G
H
J
Seal cracks
between the
fireplace
and hearth
extension with
noncombustible
material
Fireplace
Hearth
Minimum
Safety strips
Insulation
must overlap
Value "R" " minimum
G H
9" 16"
12" 20"
MINIMUM
R
K*
THICKNESS
1.09 0.50 in.**
0.458
5.0 0.10 5.46 in.**
FP533ADD
Addendum
6/1/99 djt
G
J
54"
66"
FP594MH
FP533ADD
15