Heatilator • RAVE32-IFT-B, RAVE36-IFT-B, RAVE42-IFT-B Installation Manual • 2619-983 Rev. U • 9/22
60
B. Non-Combustible Board and Drywall In-
stallation
Introduction
If the desired finished fireplace installation does not utilize
non-combustible finishing materials (such as tile, marble,
stone, etc.), special attention must be paid to the instal
-
lation of drywall/gypsum wallboard to the side joints of
the non-combustible board to minimize potential devel
-
opment of cracking and paint discoloration. Hearth and
Home Technologies has tested the following methods and
materials and therefore recommends the following steps
for the best drywall performance.
Attaching Non-Combustible Board to Framing
1. To ensure the lower cover panel has been correctly
installed, verify that two screws (total) have been
installed in the lower left and right sides of the fire
-
place opening. See Figure 8.1. These screws, when
installed, will ensure the lower panel is correctly in
-
stalled. If the lower cover panel is not correctly in
-
stalled, the decorative barrier front may not fit into the
fireplace opening correctly. Refer to section 6.D for
more information regarding the included non-combus
-
tible board.
2. The appliance ships with the required non-combus
-
tible board. The large top piece of non-combustible
board is pre-installed at the factory. The narrow left
and right non-combustible pieces are shipped within
the appliance. Install the non-combustible side pieces
with the screws provided in the manual bag assembly.
There are pilot holes located on the left and right side
columns. Care should be taken not to tighten these
screws into the non-combustible board excessively.
Set screws flush to the face of the non-combustible
board. See Figure 10.2 and Section 6.D.
3. The outer perimeter of the factory-installed non-com
-
bustible board has pre-drilled pilot holes. See Figure
10.1. Secure the non-combustible board to adja
-
cent framing with drywall screws that are a minimum
of 1-1/4 inch in length. Care should be taken not to
tighten these screws into the non-combustible board
excessively. Set screws flush to the face of the non-
combustible board. See Figure 10.2 and Section 6.D.
4. When installing drywall around the appliance, install
a rectangular hole for the fireplace/non-combustible
board in a single sheet of drywall. This will minimize
the joints that require finishing adjacent to the fireplace
opening. Ensure that the 1/8 inch gap is maintained
between the factory installed non-combustible board
and the surrounding drywall. See Figure 10.1. Secure
the drywall to the framing with screws a minimum of
one inch in length every six inches across the top of
the fireplace and every ten inches on the sides of the
fireplace.
PRE-DRILLED
PILOT HOLES
APPLIANCE
OPENING
FILL GAPS
Figure 10.1 Install Non-Combustible Board
Filling and Finishing Seams
1.
Step 1:
Fill all gaps and joints between the non-
combustible board pieces and the drywall with a
general purpose chemically setting joint compound
such as Durabond® 45 Joint Compound manufactured
by USG (Sheetrock® brand), recommended by Hearth
& Home Technologies. Use a drywall knife to firmly
press the joint compound into all gaps. See Figure
10.1. Allow these joints to dry.
2.
Step 2:
All joints are to be taped with fiberglass mesh
tape 1 7/8” minimum width, and embedded with
Setting-Type joint compound, such as with Durabond®
Joint Compound manufactured by USG (Sheetrock®
brand), or equivalent. Allow these joints to dry.
3.
Step 3:
Depending on the technique used in steps
1 and 2, two to three finishing coats are required to
provide a smooth and durable finish. Hearth and
Home Technologies recommends a lightweight or all-
purpose compound. Allow each coat to properly cure.
Allow the finishing coat(s) to cure for 24 hours before
operating appliance.
NOTICE:
Hearth & Home Technologies recommends
using multiple pieces of decorative finish material around
the opening of the appliance to reduce the chances of
the material cracking. A single piece of decorative finish
material (such as marble or granite) is more susceptible
to cracking due to uneven heating and cooling which
causes temperature differentials within the material itself.
The use of multiple pieces will reduce the temperature
differentials in each piece and reduce the likelihood of
cracks. In addition to using multiple pieces of decorative
finish material, the installation of the Passive Heat optional
heat management system will also reduce the chances of
cracking.
5. To ensure good adhesion of drywall compounds and
tape, thoroughly clean the non-combustible board and
surrounding drywall to remove dust. The non-com
-
bustible board may be primed with a high-quality PVA
primer.
