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125192-01B
9
VENTING INSTALLATION
Continued
If adapter is needed, secure it onto firestop
using holes provided (see Figure 10). The
row of holes on sides of thimble is provided
to allow for pitch variances. Position firestop
(top and bottom side) and thimble to desired
angle and secure with screws provided. Insert
thimble and firestop into prepared opening
and secure to ceiling by nailing through fire
-
stop flanges. Thimble should be even with
or above roofline. Thimble extensions are
available (as an option) when required. See
Accessories
on page 18. Firestop thimble is
not required for modular home application.
Note: If there is a second story in the home,
firestop spacer 3600FS-8DM will be required.
See Firestop Spacers, page 11.
PENETRATING ROOF
To maintain a 1" clearance to pipe on a roof
with a pitch, a rectangular opening must be
cut.
1. Determine center point through which pipe
will penetrate the roof.
2. Determine center point of the roof. Pitch
is the distance the roof drops over a given
span, usually 12". A 6/12 pitch means that
the roof drops 6" for each 12" measured
horizontally down from roof rafters.
3. Use roof opening chart (Figure 11) to
determine correct opening length and
flashing required.
4. Remove shingles around opening mea
-
sured. Cut out this section.
5. Add next sections of pipe until end pen
-
etrates roof line. Check to see that proper
clearances are maintained. Extend chim
-
ney by adding sections of double wall
pipe until pipe is minimum of 30" above
highest point of roof cutout. Termination
and chimney must extend a minimum of
36" above highest point where it passes
through roof.
Thimble (Open End)
12"
Min.
Thimble
(Closed End)
Firestop
Adapter Plate (If Needed)
Insulation
Barrier
Screw Holes
Provided
for Thimble
Firestop
Figure 10 - Use a Firestop Thimble
Assembly for Cathedral Ceiling,
Insulation Barrier and Roof
12"/96" Pitch
30"/144" Pitch
7.13"
11.77"
144"
96"
12"
30"
Thimble
Adapter Plate
(For Flat and
12"/96" Pitch
Ceilings Only)
Firestop
Use for 12"/96"
Pitch Ceiling
Use for Flat
Pitch Ceiling
14
3
/
8
"
(36.5 cm)
30"
(76.2 cm)
1"
(2.5
cm)
1"
(2.5
cm)
Minimum Measurements
1"
(2.5 cm)
Opening "A"
PITCH SLOPE
OPENING
"A" MAX
FLASHING
MODE NO.
Flat
0°
15"
6F-8
0-6/12
26.6°
16
1
/
8
"
6F-8
6/12 -
12/12
45°
20
3
/
8
"
12F-8
Figure 11 - Determine Roof Opening
