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117541-01B
10
Venting inStallatiOn
Continued
Figure 9 - Elbow Offset
B
A
Screws
FIRESTOP SPACERS (FS-10,
1100EFS-10DM FOR JM36)
Firestop spacers are required at each point where
the chimney penetrates a floor space. Their purpose
is to establish and maintain the required clearance
between the chimney and the combustible materials.
When the pipe passes through a framed opening into
a living space above, the firestop must be placed onto
the ceiling from below as shown in Figure 10.
They also provide complete separation from one floor
space to another or attic space as required by most
codes. When the double wall pipe passes through a
framed opening into an attic space, the firestop must
be placed into an attic floor as shown in Figure 11.
Figure 10 - Firestop Spacer with Living
Space Above Ceiling
Figure 11 - Firestop Spacer with Attic
Space Above Ceiling
Existing
Ceiling
Frame
Firestop
Spacer
Screws or
Staples
(Min. of 8)
Firestop
Spacer
Screws or Staples
(Min. of 8)
PENETRATING THE ROOF
To maintain a 1" (JM36) or 2" (JM42/JM50) clear
-
ance to the pipe on a roof with a pitch, a rectangular
opening must be cut.
1. Determine the center point through which the
pipe will penetrate the roof.
2. Determine the 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" one measure
horizontally down from the roof rafters.
3. Use the roof opening chart (Figure 12) to
determine the correct opening length and
flashing required.
17" Min.
30" Min.
1" Min.
1" Min.
1" Min.
Opening "A"
Roof Opening JM36
Pitch
Slope
Opening
"A" Max.
Used Flashing
Model No.
Flat
0°
17"
V6F-10DM
0-6/1
6.6°
1"
V6F-10DM
6/1-
1/1
45.0°
4"
V12F-10DM
Roof Opening JM42/50
Pitch
Slope
Opening
"A" Max.
Used Flashing
Model No.
Flat
0°
1.5"
V6F-10DM
0-6/1
6.6°
'
V6F-10DM
6/1-
1/1
45.0°
7"
V12F-10DM
Existing
Ceiling
Frame
19.5" Min.
30" Min.
2" Min.
2" Min.
2" Min.
Opening "A"
Figure 12 - Roof Opening Measurements