Notes:
(1) If an offset is necessary in the attic to avoid obstructions, it
is important to support the vent pipe every 3 feet, to avoid
excessive stress on the Elbows, and possible separation.
Wall Straps are available for this purpose (see Figure 36).
(2) Whenever possible, use 45° Elbows, instead of 90° Elbows.
The 45° Elbow offers less restriction to the flow of flue
gases and intake air.
Step 6
. Slip the flashing over the Pipe Section(s) protruding
through the roof. Use a non-hardening sealant
between the Flashing and the roof to prevent water
leakage. Secure the base of the Flashing to the
roof with roofing nails. Ensure the roofing material
overlaps the top edge of the Flashing as shown in
Figure 37. Verify that you have at least the minimum
clearance to combustibles at the roofline.
Step 7
. Continue to add Pipe Sections until the height of
the Vent Cap meets the minimum building code
requirements described by your local codes. In the
absence of local codes, make sure the terminal is
2 feet (610mm) above anything within 10 feet
(3046mm) of the vent (refer to Figure 40 & Table
3 for clearances for different pitches). Note that
for steep roof pitches, the vent height must be increased. In
high wind conditions, nearby trees, adjoining rooflines, steep
pitched roofs, and other similar factors can result in poor draft,
or down-drafting. In these cases, increasing the vent height
may solve this problem.
Step 8
. Slip the Storm Collar over the Pipe, and push it down to the top
of the Flashing, as shown in Figure 38. Use the non-hardening
sealant above and below the joint between the Storm Collar
and the Pipe.
Step 9
. Twist lock the Vent Cap.
Notes:
(1) For multi-story vertical installations, a Ceiling Firestop is required at
any subsequent floors (as shown in Figure 38). The opening should
be cut and framed in the same manner as the opening in Step 3 (see
Figure 35).
(2) Any occupied areas above the first floor, including closets and storage
spaces, which the vertical vent passes through, must be enclosed.
The enclosure may be framed and sheet rocked with standard
construction materials, however minimum allowable clearances
between the outside of the vent pipe must be maintained. Do not fill
any of the required air spaces with insulation.
Figure 38: Installation of Ceiling Fire Stops.
i
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et
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Figure 39: Typical Vent Configurations
- Vertically Terminated.
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