Venting Installation
Instructions
Continued
2.Assemble the desired lengths of pipe and elbows necessary to reach from the fireplace flue up through the firestop. All connections must be sealed with high temperature silicone sealant as specified in the second warning statement on page 11. Be sure all pipe and elbow connections are fully
3.Cut a hole in the roof using the locating hole as a center point. (Cover any exposed open vent pipes before cutting hole in roof.) The 10 3/4" x 10 3/4" hole must be measured on the horizontal; actual length may be larger depending on the pitch of the roof. There must be a 1" clearance from the vent pipe to combustible materials. Frame the opening as shown in Figure 15 on page 12.
4.Connect a section of pipe and extend up through the hole. If an offset is needed to avoid obstructions, you must support the vent pipe every 3 feet. Use wall straps for this purpose (see Figure 21, page 14). Whenever possible, use 45° elbows instead of 90° elbows. The 45° elbow offers less restriction to the flow of the flue gases and intake air.
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 21, page 14.
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 11, page 9. 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 remain- ing seam of storm collar.
Finish sealing flange around roofing material with roofing sealer.
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 24).
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 24). Align the support 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 25). Apply a bead of
Level
Cathedral ceiling support box
2" minimum below finished ceiling
Cut hole 1/8" larger than 
support box when projected onto roofline
Figure 24 - Cathedral Ceiling Support
Box Installation
Mastic under all edges of support box before nailing
Figure 25 - Installed Cathedral Ceiling
Support Box
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