Astria.us.com
126647-01_E
9
VENTING INSTALLATION
Continued
FIRESTOP SPACERS (FS-8DM)
Firestop spacers are required at each point where the chimney pen-
etrates a floor or ceiling joist 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 14. When the pipe passes through a framed opening
into an attic space above, the firestop must be placed on the attic
floor as shown in Figure 15.
IMPORTANT NOTICE
When penetrating a ceiling into an attic, a firestop thimble
(38FST or FST30) is required to avoid intrusion by insulation and
recommended to negotiate a joist (see Figure 15a, page 10).
Figure 12 - Typical Offset Installations
Figure 13 - Chimney Supports
Return
Elbow
Return
Elbow
Return
Elbow
Return
Elbow
Return
Elbow
Offset
Elbow
Offset
Elbow
Offset
Elbow
Offset
Elbow
6' (1.88 m)
Max.
6' (1.88 m)
Max.
6' (1.88 m)
Max.
6' (1.88 m)
Max.
6' (1.88 m)
Max.
6' (1.88 m)
Max.
Offset
Elbow
A
B
C
Ceiling Support
Pipe 12S-8DM
Straps
Angle
Firestop
Ceiling Support
Pipe 12S-8DM
Return
Elbow
Straps
DETAIL B
DETAIL A
See
DETAIL B
See
DETAIL A
Existing Ceiling
Frame
Firestop
Spacer
Screws or
Staples
(Min. of 8)
Firestop
Spacer
Screws or Staples
(Min. of 8)
Existing
Ceiling
Frame
Figure 14 - Firestop Spacer with Living Space Above Ceiling
Figure 15 - Firestop Spacer with Attic Space Above Ceiling