G.Vertical Termination
1.Direct Vent Pipe
WARNING
Fire Risk. Explosion Risk.
Maintain vent clearance to combustibles as speci- fied.
• Do not pack air space with insulation or other
Storm
Collar
Firestop 
Vertical Termination Cap
Flashing
Support
Box
materials.
Failure to keep insulation or other materials away from vent pipe may cause fire.
Pipe Length
Figure 5.11
Step 1.
Check the installation instructions for required 1 in. (25mm) clearances (air space) to combustibles when passing through ceilings, walls, roofs, enclosures, attic rafters, or other nearby combustible surfaces. Figure 5.17 on page
17.Check the instructions below for maximum vertical rise of the venting system, and any maximum horizontal offset limitations. All offsets must fall within the set parameters of the vent graph Figure 5.2 on page 11.
NOTE: Maximum vertical rise allowable is 40 ft. (12m) Figure 5.11.
NOTE: Maximum number of 45° elbows permitted for a vertical installation is eight, provided their installation does not decrease maximum allowable horizontal run (as specified by vent graph, on page 11).
40 ft. (12.19m) 
Maximum
Figure 5.12
Step 2.
Set the gas appliance in its desired location. Drop a plumb bob down from the ceiling to the position of the appliance flue exit, and mark the location where the vent will penetrate the ceiling. Drill a small hole at this point. Next, drop a plumb bob from the roof to the hole previously drilled in the ceiling, and mark the spot where the vent will penetrate the roof. Determine if ceiling joists, roof rafters, or other framing will obstruct the venting system. You may wish to relocate the appliance, or to offset, as shown in Figure 5.13 on page 16, to avoid cutting loadbearing members. When location is determined, drill small hole.
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