One-Piece Door - Chamberlain 1255GM Owner's Manual

Read the Safety Instructions on page 8. They also apply to doors without tracks.
• Close the door and mark the
inside vertical centerline of
your garage door. Extend the
line onto the header wall
above door.
If headroom clearance is
minimal, you can install the
header bracket on the ceiling.
See page 10.
• If you need to install the
header bracket on a 2x4 (on
wall or ceiling), use lag screws
(not supplied) to securely
fasten the 2x4 to structural
supports as shown.
Door
Jamb
Hardware
One-piece door without track
jamb hardware
• Open your door to the highest point of travel as
shown. Measure the distance from the top of the
door to the floor. Subtract the actual height of the
door. Add 8" to the remainder. (See Example).
• Close the door and draw an intersecting horizontal
line on the header wall at the determined height.
If the total number of inches exceeds the height
available in your garage, use the maximum
height possible, or refer to page 10 for ceiling
installation.
Proceed to Step 2, page 10.
ONE-PIECE Door Without Track
Header Wall
Header Wall
Highest Point
of Travel
Vertical
Centerline
2x4
Vertical
Centerline of
Garage Door
Door
One-piece door without track
Distance from top of door
(at highest point of travel) to floor...........................92"
Actual height of door ...........................................– 88"
Remainder................................................................4"
Add ........................................................................+ 8"
Bracket height on header wall .............................= 12"
(Measure UP from top of CLOSED door.)
9
Unfinished
Ceiling
2x4
OPTIONAL CEILING MOUNT
FOR HEADER BRACKET
Highest Point
Header
of Travel
Wall
Pivot
pivot hardware
EXAMPLE
Structural
Supports