DuraVent Venting System For Direct Vent Pro - Manual (Page 14)

14
Figure 15
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.
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
(Fig. 15).
(2) If an offset is necessary in the attic
EXTENSION
PIPE
SECTION
PIPE
to avoid obstructions, it is important to
support the vent pipe in order to avoid
excessive stress on the Elbows. Wall
Straps or plumbers tape may be used
for this purpose (Fig. 16).
(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 7. 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. Ensure
the roofing material overlaps the
top edge of the Roof Flashing (Fig.
18). Verify that you have at least the
minimum clearance to combustibles at
the roofline and in the attic.
Step 8. Continue to add Pipe Sections
until the height of the system (before
adding the Cap) meets the minimum
building code requirements as
described in (Table 3 and Fig. 17).
Note that for steep roof pitches, the
vent height must be increased. In
high wind conditions, nearby trees,
Figure 14
JOISTS
CEILING
CUT
AND FRAME
DECORATIVE
COVER
1 1/2"
WOOD SCREWS
SUPPORT
CEILING
FRAMING
JOISTS
CEILING
CUT
AND FRAME
DECORATIVE
COVER
1 1/2"
WOOD SCREWS
SUPPORT
CEILING
FRAMING