Installation Guide

9
Table 2
Figure 10
Figure 8
FRAMING
FIRESTOP
RADIATION SHIELD
Figure 9
TWIST CLOCKWISE
TO TIGHTEN
ATTIC INSULATION
SHIELD
Framing Dimensions
Chimney Diameter
5” 6” 7” 8”
CATHEDRAL CEILING
SUPPORT BOX
111/4” 121/4” 131/4” 141/2”
FLAT CEILING
SUPPORT BOX
111/4” 121/4” 131/4” 141/2”
ROUND CEILING
SUPPORT BOX
111/4” 121/4” 131/4” 141/4”
FIRESTOP RADIATION
SHIELD
111/4” 121/4” 131/4” 141/4”
WALL THIMBLE 111/4” 121/4” 131/4” 141/4”
CAS CEILING
SUPPORT
NA 121/4” NA 141/2”
CAS WALL THIMBLE NA 121/4” NA 141/4”
REDUCED
CLEARANCE
SUPPORT BOX
NA 101/4” NA NA
above that where the Support Box is located.
Example: in a multistory home where the
appliance is on the ground oor (Support
Box is in the 1st oor ceiling), you would
need a Firestop Radiation Shield at the 2nd
oor ceiling, and at the 3rd oor ceiling, etc.,
including where the chimney penetrates into
the attic. Figure 7 shows a typical 2-story
installation with an attic.
Note: a Firestop Radiation Shield is not
installed where the chimney penetrates
through the roof. The Firestop Radiation
Shield is installed on the underside of the
ceiling/oor framing, with the cylindrical
“tube” portion of the shield pointing
upward. (Fig 8). Use a minimum of either
(1) 8 penny nail or (1) #8, 1-1/2” wood screws
per corner. Refer to Table 2 for framing
requirements.
opening and maintain the 2-inch clearance to
combustibles.
6. Install Firestop Radiation Shield: A
Firestop Radiation Shield is required in
multistory installations at each oor penetration