VENTING INSTALLATION
Continued
FIRESTOP SPACERS
Firestop spacers are required at each point where chimney penetrates a floor space. Their purpose is to establish and maintain required clearance between chimney and combustible materials. When pipe passes through a framed opening into a living space above, firestop must be placed onto ceiling from below as shown in Figure 12.
They also provide complete separation from one floor space to another or attic space as required by most codes. When double wall pipe passes through a framed opening into an attic space, firestop must be placed into an attic floor as shown in Figure 13.
If area above is a living space, install
firestop below framed hole.
4.Remove shingles around opening mea- sured. Cut out this section.
5.Add next sections of pipe until end penetrates roof line. Check to see that proper clearances are maintained. Extend chimney 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.
Minimum Measurements |
| |
16 3/8" |
| |
(48.3 cm) | 30" | |
2" | ||
(76.2 cm) | ||
(5.1 | 2" | |
cm) | ||
(5.1 cm) | ||
| ||
2" |
| |
(5.1 |
| |
cm) |
|
Figure 12 - Firestop Spacer with Living
Space Above Ceiling
Opening "A"
If area above is an attic or insulated area,
install firestop above framed hole.
Figure 13 - Firestop Spacer with Attic
Space Above Ceiling
PENETRATING ROOF
To maintain a 2" clearance to pipe on a roof with a pitch, a rectangular opening must be cut.
1.Determine center point where 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" measure horizontally down from roof rafters.
3.Use roof opening chart (Figure 14) to determine correct opening length and flashing required.
Pitch | Slope | Opening | Used Flashing |
|
| "A" Max. | Model No. |
Flat | 0° | 15" | |
26.6° | 16 1/8" | ||
6/12- 12/12 | 45.0° | 20 3/8" |
Figure 14 - Roof Opening Measurements
FLASHING INSTALLATION
Determine flashing to be used with roof opening chart. Slide flashing over pipe until base is flat against roof. Replace as many shingles as needed to cover exposed area and flashing base. Secure in position by nailing through shingles (see Figure 15, page 11). DO NOT NAIL THROUGH FLASHING CONE.
Installing Flashing on a Metal Roof When installing flashing on a metal roof, it is required that putty tape be used between flashing and roof. Flashing must be secured to roof using #8 x 3/4" screws and then sealed with roof coating to prevent leakage through screw holes. A roof coating must also be applied around perimeter of flashing to provide a proper seal.
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