Venting Installation
Instructions
Continued
5.Place the flashing over the pipe section(s) extending through the roof. Apply a bead of silicone or roof sealer to the bottom flange of flashing and secure the base of the flashing to the roof and framing with roofing nails. Be sure roofing material overlaps the top edge of the flashing as shown in Figure 24, page 15.
There must be a 1" clearance from the vent pipe to combustible materials.
6.Continue to add pipe sections until the height of the vent cap meets the minimum building code requirements described in Figure 14, page 10. Note: You must increase vent height for steep roof pitches. Nearby trees, adjoining rooflines, steep pitched roofs, and other simi- lar factors may cause poor draft or
7.Apply a bead of sealer to the upper edge of flashing collar. Slide storm collar over pipe and down to top edge of flashing. Apply a second bead of silicone or roof sealer around remaining seam of storm collar.
Note: If the vent pipe passes through any occupied areas above the first floor, including storage spaces and closets, you must enclose pipe. You may frame and sheetrock the enclosure with standard construc- tion material. Make sure and meet the minimum allowable clearances to combustibles. Do not fill any of the required air spaces with insulation.
Cathedral Ceiling Installation
1. Remove shingles or other roof covering as necessary to cut the rectangular hole for the support box. Mark the outline of the cathedral ceiling support box on the roof sheathing using the locating hole as a center point.
2. Cut the hole 1/8" larger than the support box outline (see Figure 27).
3. Lower the support box through the hole in the roof until the bottom of the box extends at least 2" below the ceiling (see Figure 27). Align the sup- port box vertically and horizontally using a level. Temporarily tack the support box in place through the inside walls and into the roof sheathing.
4. Using tin snips, cut the support box from the top corners down to the roofline and fold the resulting flaps over the roof sheathing (see Figure 28). Apply a bead of
5. Complete the cathedral ceiling installation by following the same procedures outlined in steps 2 through 7 for Flat Ceiling Installation, page 16.
Level
Cathedral ceiling support box
2" minimum below finished ceiling
Cut hole 1/8" larger than 
support box when projected onto roofline
Figure 27 - Cathedral Ceiling Support
Box Installation
Mastic under all edges of support box before nailing
Figure 28 - Installed Cathedral Ceiling
Support Box
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