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*For systems with two elbow sets, the minimum height is 22
feet. The maximum height for any system is 50 feet.
OFFSET CHART (22-50 FT. SYSTEM HEIGHT)
FIRESTOP SPACERS (FS-8DM)
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.
PENETRATING THE ROOF
OFFSET
RISE
A
B
48"
36"
24"
18"
12"
4 - 3/8
16 -3/8
9 - 3/4
25 - 1/2
1
12 - 3/4
30 - 3/4
1
15
34 - 3/4
1
18
40
1
1
21 - 1/4
46 - 1/4
1
23 - 3/4
49 - 1/4
1
1
27 - 3/4
56 - 3/4
1
30
60 - 3/4
1
1
33
66 1
1
36
71
1
1
38 - 1/4
75
2
41 - 1/4
80 - 1/4
1
1
1
45
86 - 3/4
2
46 - 3/4
89 - 1/2
1
1
1
51
97
1
1
53 - 1/4
101
2
1
56 - 1/4
106 - 1/4
2
59 - 1/4
111 - 1/2
1
1
1
61 - 3/4
115 - 1/2
2
1
64 - 3/4
120 - 3/4
2
1
68 - 1/4
127
1
2
70
130
2
1
1
74 - 1/4
137 - 1/2
1
2
1
76 - 3/4
141 - 1/2
1
2
1
79 - 3/4
146 - 3/4
4
ELBOW SET ONLY
CHIMNEY LENGTH
Figure 8 CEILING SUPPORT PIPE
Figure 9 ELBOW OFFSET
All pipe connections between the offset and return
must be secured with two screws, only on the outer
pipe, and shall not penetrate the inner stainless.
Figure 7
*TYPICAL OFFSET INSTALLATION
Figure 10 FIRESTOP SPACER
Figure 11 FIRESTOP SPACER
