Finish Wall, Side Wall Protection | Vermont Casting CR36R, CR36L

CR Series Woodburning Fireplaces

Finish Wall

Finish the wall with material of your choice. Do not install a combustible mantel shelf less than 12” (305mm) from the top of the ﬁreplace opening. Do not install a mantel face plate less than 6” (159mm) from top of ﬁreplace opening. (Fig. 18) If a combus- tible material is used below a ﬂat mantel shelf, consult your local building codes for minimum clearance from top of ﬁreplace opening to bottom of mantel shelf.

When ﬁnishing the ﬁreplace, a combustible facing ma- terial (i.e. drywall or wood paneling) may be installed at the ﬁreplace surround top as shown in Figure 20. This material may rest on the ledge brackets (brackets on the front and side edges of the ﬁreplace), but must NOT be notched to ﬁt around them. (Fig. 20)

All joints (top, bottom and sides), where the wall or decorative facing material meets the ﬁreplace sur- round must be completely sealed with a noncombus- tible material. (Fig. 17, 18, 20)

Only noncombustible material may be applied as fac- ing to the black ﬁreplace surround.

When ﬁnishing the ﬁreplace, never obstruct or modify the air inlet grille in any manner.

When ﬁnishing the ﬁreplace, use the material of your choice. If you decide to cover the ﬁreplace surround, noncombustible materials must be used.

Side Wall Protection

All walls constructed closer than 16” (406mm) from the ﬁreplace opening must be protected with CFM Corpo- ration Wall Shield Model SP40 or a built-up wall shield described in Figure 17.

(ANY PERPENDICULAR SIDE WALL MUST NOT BE CLOSER THAN 40” (1016mm) TO THE OPEN END OF AN OPEN END FIREPLACE.)

The built-up wall shield design described in Figure 17 is an alternate method for adding protection to side walls and can be used in place of the SP40 with the same wall clearances speciﬁed for the SP40.

EXAMPLES OF INSULATION:

1.Manville - CERAFORM 126, K = .27, 1/2” thick required.

2.CFM Corporation Building Products - EH2416, K =

.458, 1” thick required.

Hearth Installation

A hearth extension is required to protect a combustible ﬂoor in front of the ﬁreplace. Refer to Figure 20 for minimum dimensions and mounting detail.

NOTE: Hearth Extension must not cover the air inlet opening of a ﬁreplace.

The hearth extension described in Figure 20 must be a durable non-combustible material with a minimum (to- tal) Rt value of 1.09; refer to Figure 21 for examples.

The overall height (above a combustible ﬂoor), depth and width must be as indicated, with the extension centered to the ﬁreplace opening.

The top of the insulation material must be covered with a noncombustible decorative covering or a piece of

.018” minimum sheet metal, to protect hearth exten- sion material. (Fig. 23)

Secure the hearth extension to the ﬂoor to prevent shifting, using trim molding or other similar means at three (3) outer edges. Seal crack between the ﬁre- place hearth and hearth extension with a noncombus- tible material. (Figs. 22,23)

WARNING: HEARTH EXTENSION MUST BE INSTALLED IN ACCORDANCE WITH FIGURES 20 AND 21.

Alternate noncombustible materials may be used pro- viding the (total) thermal resistance (Rt value) of the alternate material employed is greater than or equal to R = 1.09. Thermal resistance (R) or thermal conduc- tivity (K), may be obtained from manufacturer of the material. Factors are related by the formula K = 1/R.

T = given thickness

R = thermal resistance for a given thickness (T)

K = thermal conductivity

Noncombustible material with a lower R value may be used, provided thickness of material is sufﬁciently greater to maintain an equivalent (total) thermal resis- tance (Rt).

Example of Determining Hearth Extension Equivalents

To determine the thickness required for any new mate- rial:

NEW		K of new material (per inch)	thickness
required	=		X of listed

thickness		K of listed material (per inch)	material

Example for Common Brick

T (new) = 5.0/0.458 x .5 in. = 5.46 in. (new required thickness).

20001316