37Heatilator • CD4236IR-C, CD4842IR-C • 2207-900 Rev. J • 11/11
A*
B*
10 in.
12 in.
C
D
10 in.
12 in.
A. Pipe Clearances to Combustibles
WARNING! Risk of Fire! Maintain air space clearance to
vent. DO NOT pack insulation or other combustibles:
• Between ceiling fi restops
• Between wall shield fi restops
• Around vent system
Failure to keep insulation or other material away from
vent pipe may cause over heating and fi re.
8
8
Vent Clearances and Framing
Figure 8.2 Wall Penetration
* Shows center of vent framing hole for top or rear venting. The center of the
hole is one (1) in. (25.4 mm) above the center of the horizontal vent pipe.
Figure 8.1 Horizontal Venting Clearances To Combustible
Materials
* When using SLP or SL-D pipe, minimum clearances from the vent pipe to combus-
tible materials at inside wall firestops are: Top: 2-1/2 in. (64 mm)
Bottom: 1/2 in. (13 mm)
Sides: 1 in. (25 mm)
Note: Heat shields MUST overlap by a minimum of 1-1/2 in. (38 mm).
• DVP heat shield - designed to be used on a wall 4 in. to 7-1/4 in. (102 mm to 184
mm) thick.
• If wall thickness is less than 4 in. the existing heat shields must be field trimmed. If
wall thickness is greater than 7-1/4 in. a DVP-HSM-B will be required.
• SLP heat shield - designed to be used on a wall 4-3/8 in. to 7-5/8 in. (111 mm to
194 mm thick).
• If wall thickness is less than 4-3/8 the existing heat shields must be field trimmed.
If wall thickness is greater than 7-5/8 in. a DVP-HSM-B will be required.
(DVP-SLP Pipe Shown)
3 in. (76 mm)
top clearance *
1 in. (25 mm)
clearance
bottom & sides
Heat
Shield
Wall
Shield
Firestop
Heat
Shield
WALL
3 in. (76 mm)
top clearance *
1 in. (25 mm)
clearance
bottom & sides
Heat
Shield
Wall
Shield
Firestop
Heat
Shield
WALL
3 in. (76 mm)
top clearance
1 in. (25 mm)
clearance around
vertical sections
A* B* C D
CD4236
in. 42-3/4 27-7/8 41-3/4 26-7/8
mm 1086 708 1060 683
CD4842
in. 44-3/4 29-7/8 44-1/8 28-7/8
mm 1137 759 1111 733
B. Wall Penetration Framing
Combustible Wall Penetration
Whenever a combustible wall is penetrated, you must
frame a hole for the wall shield fi restop(s). The wall shield
fi restop maintains minimum clearances and prevents cold
air infi ltration.
• The opening must be framed on all four sides using the
same size framing materials as those used in the wall
construction.
• SLP pipe - A wall shield fi restop must be placed on each
side of an interior wall. A minimum 1-1/2 in. (38 mm)
overlap of attached heat shields must be maintained.
• DVP pipe - A wall shield fi restop is required on one side
only on interior walls. If your local inspector requires a
wall shield fi restop on both sides, then both wall shield
fi restops must have a heat shield (refer to Section 16.B.)
attached to them.
• See Section 10.L. for information for regarding the in-
stallation of a horizontal termination cap.
Non-Combustible Wall Penetration
If the hole being penetrated is surrounded by noncom-
bustible materials such as concrete, a hole with diameter
one inch greater than the pipe is acceptable.
Whenever a non-combustible wall is penetrated, the wall
shield fi restop is only required on one side and no heat
shield is necessary.