Chamberlain LiftMaster Security+ 2500B Owner's Manual page 21

ONE-PIECE DOORS
Please read and comply with the warnings and
reinforcement instructions on the previous page.
They apply to one-piece doors also.
• Center the door bracket on the top of the door, in
line with the header bracket as shown. Mark either
the left and right, or the top and bottom holes.
• Metal Doors: Drill 3/16" pilot holes and fasten the
bracket with the 1/4"-14x5/8" self-threading screws
provided.
• Wood Doors: Drill 5/16" holes and use 5/16"x2"
carriage bolts, lock washers and nuts (not
provided) or 5/16"x1-1/2" lag screws (not
provided) depending on your installation needs.
NOTE: The door bracket may be installed on the top
edge of the door if required for your installation.
(Refer to the dotted line optional placement
drawing.)
Header Wall
Header
Bracket
Door
Bracket
Vertical
Centerline of
Garage Door
Finished Ceiling
2x4 Support
Optional
HORIZONTAL AND VERTICAL
Placement
REINFORCEMENT IS NEEDED
of Door
FOR LIGHTWEIGHT GARAGE
Bracket
DOORS (FIBERGLASS,
ALUMINUM, STEEL, DOORS
WITH GLASS PANEL, ETC.).
(NOT PROVIDED)
For a door with no exposed framing,
or for the optional installation, use
lag screws 5/16"x1-1/2" (Not Provided)
to fasten door bracket.
Door
Bracket
Nut
5/16"-18
Door
Bracket
21
HARDWARE SHOWN
ACTUAL SIZE
Self-Threading Screw
1/4"-14x5/8"
Self-Threading
Screw
1/4"-14x5/8"
Top of Door
(Inside
Garage)
Top Edge
of Door
Optional
Placement
METAL DOOR
Lock
Washer
5/16"
Top of Door
(Inside
Garage)
Top Edge
of Door
Optional
Placement
Carriage Bolt
5/16"x2"
(Not Provided)
WOOD DOOR