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3-90-30007474
Vermont Castings • Intrepid DV-IFT Owner’s Manual_R20 • 11/21
In these cases, increasing the vent height or switching to the
high wind termination cap may help to solve the problem.
Step 8
- Slip the storm collar over the pipe section, and
push it down to the top of the roof flashing, Figure 3.37.
Use non-hardening sealant between the storm collar and
the pipe section
Step 9
- Holding the bottom of the termination cap only, twist
lock the cap onto the last pipe section protruding above the
roofline.
NOTES:
1. For multi-story vertical installations, a ceiling firestop is
required at the second floor, and any subsequent floors,
Figure 3.22. Cut and frame a 9” x 9” (229 mm x 229 mm)
square opening for installation of the ceiling firestop.
2. If vent passes through any occupied areas above the
first floor, including closets and storage spaces, it must
be enclosed. The enclosure may be framed and covered
with sheet rock with standard construction materials, but
required clearances to combustibles must be maintained.
Table 2
Roof Pitch
Minimum Height
Flat 7/12
1' (914 mm)
Over 7/12 to 8/12
1' 6" (457 mm)
Over 8/12 to 9/12
2’ (610 mm)
Over 912 to 10/12
2’ 6” (762 mm)
Over 10/12 to 11/12
3’ 3” (990 mm)
Over 11/12 to 12/12
4’ (1.2 m)
Over 12/12 to 14/12
5’ (1.5 m)
Over 14/12 to 16/12
6’ (1.8 m)
Over 16/12 to 18/12
7’ (2.1 m)
Over 18/12 to 20/12
7’ 3” (2.3 m)
Over 20/12 to 21/12
8’ (2.4 m)
Ensure the roofing material overlaps the top edge of the
roof flashing, Figure 3.37. Verify that you have at least the
minimum clearances to combustibles at the roofline and in
the attic.
Step 7
- Continue to add pipe sections until the height of
the system (before
adding the cap) meets
the minimum building
codes requirements
as described in Table
2, Figure 3.36. 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.
Figure 3.36
H
ST989
chimney height
8/07
Dimension ‘H’ from
Table 2
NOTES:
1. If exact lengths or
distances must be met
between elbow offsets or
elsewhere, use the pipe
extensions to adjust onto
standard pipe sections,
Figure 3.34.
2. If an offset is necessary
in the attic to avoid
obstructions, it is
important to support
the vent pipe in order to
avoid excessive stress
on the elbows. Wall
straps or plumber tape
may be used for this
purpose, Figure 3.35
3. Wherever 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 roof flashing over the pipe section(s)
protruding through the roof. Use a non-hardening sealant
between the roof flashing and the roofing to prevent water
leakage. Secure the base of the roof flashing to the roof with
roofing nails.
ST988
offset
8/07
Wall Strap /
Plumbers Tape
45° Elbow
45° Elbow
Figure 3.35
ST986
thru ceiling
8/07
Ceiling Joists
Cut and
Frame
1-1/2" Wood
Screws
Decorative
Ceiling Support
Cover
Figure 3.33
Continue to assemble
pipe sections and elbows
as necessary to reach
up through the roofline.
Galvanized pipe and
elbows may be utilized in
the attic, as well as above
the roofline. The galvanized
finish is desirable above
the roofline, due to higher
corrosion resistance.
Figure 3.34
ST987
pipes
8/07
Pipe
Extension
Pipe
Section
