
19
Horizontal / Inclined Run
Support Brackets
Building
Support
Framing
SV4.5E90
Elbow
Ceiling  Firestop / Spacer
SV4.5VF
 When Using Secure Flex, 
Use Firestop / Spacer SF4.5VF
Fireplace
SV4.5L6/12/24/36/48
Vent Sections
Vertical
Rise
SV4.5HT-2
Termination
Shown
Support Bracket Spacing
Every 5 ft (1.52 m)
Exterior
Wall
SV4.5HT-2
Termination
Shown
Figure 31 - TYPICAL HORIZONTAL VENT INSTALLATION
See Figure 18 on Page 14 or Figure 21 on 
Page 15  for vertical vent section support.
B. Frame exterior wall opening - 
Locate the center of the vent outlet on 
the exterior wall according to the dimen-
sions shown in Figure 14 on Page 11.  Cut 
and/or frame an opening, 10-1/2" x 12-1/8" 
(267 mm x 308mm) inside dimensions, about 
this center. 
C. Frame ceiling opening - If the vertical route 
is to penetrate a ceiling, use plumb line to locate 
the center above the appliance. Cut and/or frame 
an opening, 10-1/2" x 10-1/2" (267 mm x 267 
mm) inside dimensions, about this center (refer 
to Figure 19 on Page 15).
D. Attach vent components to appliance - To 
attach a vent component to the appliance collar, 
align the dimpled end over the collar, adjust-
ing the radial alignment until the four locking 
dimples are aligned with the inlets of the four 
incline channels on the collar (refer to Figure 
20 on Page 15).
Push the vent component against the collar 
until it fully engages, then twist the component 
clockwise, running the dimples down and along 
the incline channels until they seat at the end 
of the channels.
The unitized design of the Secure Vent 
components will engage and seal both the 
inner and outer pipe elements with the same 
procedure.  Sealant and securing screws are 
not required.
Note: An elbow may also be attached to the 
appliance collar.  Attach in the same manner 
as you would a vent section. 
E. Attach vent components to each other 
- Other vent sections may be added to the pre-
viously installed section in accordance with the 
requirements of the vent tables.  To add another 
vent component to a length of vent run, align the 
dimpled end of the component over the inclined 
channel end of the previously installed section, 
adjusting the radial alignment until the four lock-
ing dimples are aligned with the inlets of the four 
incline channels of the previous section.  
Push the vent component against the previous 
section until it fully engages, then twist the 
component clockwise running the dimples down 
and along the incline channels until they seat at 
the end of the channels.This seating position 
is indicated by the alignment of the arrow and 
dimple as shown in Figure 20 on Page 15.
F. Install fi restop/spacer at ceiling - 
When using Secure Vent, use SV4.5VF fi restop/
spacer at ceiling joists; when using Secure Flex, 
use SF4.5VF fi restop/spacer. 
If there is living space above the ceiling level, 
the fi restop/ spacer must be installed on the 
bottom side of the ceiling. If attic space is 
above the ceiling, the fi restop/ spacer must be 
installed on the top side of the joist. Route the 
vent sections through the framed opening and 
secure the fi restop/spacer with 8d nails or other 
appropriate fasteners at each corner.
Remember to maintain 1" (25 mm) clearance 
to combustibles, framing members, and attic 
or ceiling insulation when running vertical 
chimney sections.
G. Support the vertical run sections - 
See Section E on Page 15.
H. Change vent direction  - At transition from or 
to a horizontal/inclined run, install the SV4.5E45 
and SV4.5E90 elbows in the same manner as 
the straight vent sections.  The elbows feature a 
twist section to allow them to be routed about the 
center axis of their initial collar section to align 
with the required direction of the next vent run 
element. Twist elbow sections in a clockwise 
direction only so as to avoid the possiblity of 
unlocking any of the previously connected vent 
sections. See Figure 22 on Page 16.
I. Continue installation of horizontal/inclined 
sections -  Continue with the installation of the 
straight vent sections in horizontal/inclined run 
as described in Step E. Install support straps 
every 5 ft. (1.52 m) along horizontal/inclined 
vent runs using conventional plumber’s tape. 
See Figure 31. It is very important that the 
horizontal/inclined run be maintained in a 
straight (no dips) and recommended to be in 
a slightly elevated plane, in a direction away 
from the fi replace of 1/4" rise per foot (20 mm 
per meter) which is ideal, though rise per foot 
run ratios that are smaller are acceptable all the 
way down to at or near level.
It is important to maintain the required clear-
ances to combustibles: 1" (25 mm) at all sides 
for all vertical runs; and 3" (76 mm) at the top, 
1" (25 mm) at sides, and 1" (25 mm) at the 
bottom for all horizontal/inclined runs.