How to Install the Inner Slide Lock on an Overhead Garage Door

When installing a garage door opener and a garage door, it is a practice among professional installers to not install a center key lock.

This helps prevent damage to the door due to someone accidentally locking the door. However, many homeowners want added security in the event the door opener must be disconnected from the door due to a power outage. Installing an inner slide lock on an overhead garage door is a quick process and enables you to have the added security you need when the door is in manual operation.

Disengage the opener trolley from the carriage by pulling on the emergency release rope. Grab the inner door lock and push the slide bolt so that it is fully extended. The curve of the slide bolt should be against the side of the lock body when you fully extend the slide bolt.

Place your foot on the top of the bottom roller on the right side of the door. Press down with your foot and hold the door down. This compresses the bottom seal so that you get a tight seal when locking the door.

Position the inner slide lock on the end of the second door panel, with the slide bolt protruding through the hole on the side track. The body of the lock should be straight. Reposition as necessary so that the top of the slide bolt is below the top of the track lock hole without touching.

Mark the mounting holes from the lock onto the door panel with a pencil. Place the lock aside and drill holes at your marks with a 3/16-inch drill bit. If drilling a steel door, drill through the front of the end stile but not through the door. If drilling in a wood door, only drill 1/2 inch deep.

Place the lock against the end of the door and line up the mounting holes with the pilot holes. Secure the lock to the door with #14 by 5/8-inch hex sheet metal screws and a socket wrench if installing on a steel door. Use 1-inch long 1/4 inch wood screws if installing on a wood door.

Pull the lock lever to the left to disengage the lock bolt from the track. Engage the opener trolley back onto the opener carriage until you hear and feel it click into position.

Things You Will Need

  • Pencil
  • Drill with 3/16-inch drill bit
  • Socket wrench
  • 4 #14 by 5/8-inch hex head sheet metal screws (for steel doors)
  • 1-inch by 1/4-inch wood screws (for wood doors)


  • Never engage the slide lock while the door opener is engaged to the door.

About the Author

Kenneth Crawford is a freelance writer with more than 10 years of experience. His work has appeared in both print and online publications, including "The American Chronicle." Crawford holds an associate degree in business administration from Commonwealth College.