Venting Installation
instructions
Continued
5. Place the flashing over the pipe section(s) extending through the roof. Secure the base of the flashing to the roof and framing with roof- ing nails. Be sure roofing material overlaps the top edge of the flashing as shown in Figure 19, 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 9 on page 9. Note:You must increase vent height for steep roof pitches. Nearby trees, adjoining rooflines, steep pitched roofs and other similar factors may cause poor draft or
7.
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.
Thimble Installation
1. Plumb and locate knockout area for vent pipe.
2. Cut and frame ceiling joist to dimensions shown in Figure 11, page 11.
3. Determine where firestop plate should be at- tached to thimble by
4. Attach thimble into firestop plate using 4 hex screws provided (see Figure 21).
5.Refit assembly into opening and attach to framing with 8 phillips screws provided (see Figure 20, page 15).
6.Thimble installation is ready to receive vent pipe. Follow venting installation instructions.
Vertical Termination Configurations for
Top Vent
Figures 22 through 25 show four different con- figurations for vertical termination.
VERTICAL VENT INSTALLATIONS USING MULTIPLE 90° ELBOWS
Note: Install a
section prior to
attaching vent
termination cap.
90° Elbow
Top of
Thimble
Should
Measure 
to Top of Insullation
Framing
Hex Screw to Attach 
Firestop to Thimble
Venting with Three 90° Elbows
| Horizontal (H1) + |
Vertical (V) | Horizontal (H2) |
8' Min. | 5' Max |
10' Min. | 8' Max |
12' Min. | 11' Max |
14' Min. | 14' Max |
16' Min. | 17' Max |
18' Min. | 20' Max |
40' Min. | 20' Max |
Phillips Screws
Firestop 
to Attach Firestop to
Framed Hole
Figure 21 - Installing Thimble with
Firestop
Figure 22 - Vertical Venting
Configuration using Three 90° Elbows (Vertical Round High Wind Termination)
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