Inserting Damper into Wall/Floor Openings
Figures 5 - 7
show installations for grille access and continuing duct applications.
The following maximum distances outside the barrier apply:
• Steel stud and masonry barriers:
- 8
1
⁄
2
in. (216 mm) provided the width and height of the damper are both 24 in. (610 mm) or less and the
damper sleeve is 20 gauge
- 7
1
⁄
2
in. (191 mm) in all other instances
• Wood stud walls: 6
1
⁄
2
in. (165 mm)
To provide "through the grille" access to the damper actuator, the damper is located toward the back of the sleeve
and the actuator is installed between the damper and grille. Actuator and damper can be accessed and serviced by
removing the grille. To provide access to the damper actuator for continuing ductwork, refer to the requirements of
NFPA 90A.
Figure 7: Continuing Duct - Horizontal or Vertical Mount
Figure 5: Through the Grille Access - Duct Terminates
Metal Stud
Wooden Stud Construction
Gypsum Wallboard
Stud or Runner
Retaining
Angle
(Duct Terminates)
In wood stud construction,
gypsum wallboard must cover
all wood stud surfaces.
Grille
(Supplied
by others)
Factory Supplied
Thermal Blanket
Fire damper or
combination fire
smoke damper
6 1/2 in.
Max.
#10 sheet metal
screws, 2 1/2 inches
long, spaced 6 in. on
center and maximum
of 2 in. from corners
(minimum of 2 screws
per side). Screw into
rear portion of the
studs so as to avoid
space conflicts with
the grille assembly.
Figure 6: Through the Grille Access - Duct Terminates
Wood Stud
Factory Supplied
Thermal Blanket
7 1/2 in. max. or
8 1/2 in. max.*
Damper
Masonry
floor
Steel stud
Flange
Grille
(Supplied
by others)
Factory Supplied
Thermal Blanket
7 1/2 in. Max.
or
8 1/2 in. Max.*
Damper
#10 2 1/2 in. long sheet metal
screws spaced 6 in. on center and
maximum of 2 in. from the corners
(minimum of 2 screws per side)
through the sleeve into the header,
sill and jamb framing members.
Screw into rear portion of the
studs so as to avoid space
conflicts with the grille assembly.
*
The out of wall/floor limitation for
steel stud and masonry barriers
is 7
1
⁄
2
in. (191 mm) except in
instances where both the width
and height of the damper is 24
in. (610 mm) or less and when
the damper sleeve is 20 gauge in
which case the damper may be
up to 8
1
⁄
2
in. (216 mm) out of the
barrier.
For more installation methods that are approved for ODFD-XXX and OFD-XXX series, go to www.greenheck.com.
For access to inspect the damper and fusible link refer to the requirements of NFPA 90A.
Out of Wall Fire and Combination Fire Smoke Dampers
5
®
