Venting Installation
|
| Continued |
|
| See Detail A |
|
| 2" Min. |
Straps | Straps |
|
Detail B |
| |
Angle Firestop | See Detail B | |
Existing
Ceiling
Frame
Firestop 
Spacer
Screws or Staples (Min. of 8)
Figure 10 - Firestop Spacer with Living
Space Above Ceiling
Straps Straps
Detail A
Return Elbow
Figure 8 - Ceiling Support Pipe
Screws
B
A
Figure 9 - Elbow Offset
Firestop Spacers
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.
Screws or Staples
Firestop(Min. of 8)
Spacer
Existing
Ceiling
Frame
Figure 11 - Firestop Spacer with Attic
Space Above Ceiling
Penetrating roof
To maintain a 1" clearance to the pipe on a roof with a pitch, a rectangular opening must be cut.
1.Determine center point through which pipe will penetrate roof.
2.Determine center point of 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 roof opening chart (Figure 12, page 9) to determine the correct opening length and flashing required.
4.Remove the shingles around opening measured. Cut out this section.
5.Add next sections of pipe until end pen- etrates roof line. Check to see that the proper clearances are maintained. Extend chimney by adding sections of double wall pipe until pipe is minimum of 30" above the highest point of the roof cutout. Termination and chimney must extend a minimum of 36" above the highest point where it passes through the roof.
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