Preparation Of Openings; Clearances Required Between Corridor Damper Sleeves And Ceiling Openings; Maximum Assembly Table - Greenheck CFSD Series Installation, Operation And Maintenance Manual

Preparation of Openings

• Corridor dampers are rated in ceiling constructions with a fire resistance rating of one hour.
• Frame corridor openings as shown below. Maximum size of opening is 24 in. x 24 in. (610 mm x 610 mm).
(see Figure 1 & 2).
• Corridor ceiling must be covered with a minimum of one sheet of
• All construction and fasteners must meet the requirements of the appropriate corridor ceiling design. Gypsum
panels should be attached, 12 in. (305 mm) O.C. maximum, to all stud and runner flanges surrounding opening
with fasteners as designated by the appropriate corridor ceiling design. (See UL Fire Resistance Directory) and/
Steel Stud Assembly
or local codes.
24 in. o.c. max.
Opening lined
with UL rated
5/8 in. gypsum
board
Wood Stud Assembly
Figure 1
Clearances Required Between Corridor Damper Sleeves and Ceiling
Openings
The interior dimension of the prepared ceiling opening should be
damper and sleeve assembly.
These are total clearances (ignoring fastener heads) and do not need to be spaced equally around the damper.

Maximum Assembly Table

®
24 in.
Steel
studs
max.
2 in. x 4 in.
(nominal)
wood studs
24 in.
max.
Horizontal Mount
Damper Model
CFSD-211, -212
⁄ in. UL rated gypsum board on both sides.
5
8
24 in. o.c. max.
Steel Stud Assembly
Figure 2
24 in. o.c. max.
Opening lined
with UL rated
⁄ in. (6 mm) larger than the overall size of the
1
4
5/8 in. gypsum
board
Wood Stud Assembly
Maximum Single
Section Size
(inches)
24 x 24
24 in.
Steel
studs
max.
2 in. x 4 in.
(nominal)
wood studs
24 in.
max.
CFSD Series 3