How to Install Bi-Fold Doors for an Uneven Opening

Go to the inside of the bi-fold doors, and fully shut the doors.

Place the end of a tape measure against the floor, below where the two lead bi-fold door panels meet when shut. Extend the tape measure up 6 inches.

Mount a door aligner onto the inside edge of each of the lead door panels at the 6-inch mark. Use a power drill to install the mounting screws for the door aligners.

Go to the outside of the bi-fold doors and shut them.

Measure from the floor to the bottom edges of each of the door panels. Also, measure the distance from the outside door edges to the left and right door jambs. Examine where the lead door panels meet, and see whether they press tightly together or if a lot of space exists between them.

Lift up on the bi-fold doors and slide the bottom hinge pin, which is inside the slot in the floor bracket, toward the door center or toward the jamb. Slide it toward the center if too much of a gap exists between the lead door panels; slide it toward the jamb if the panels press against each other.

Remove the bi-fold doors if this does not solve the problem or if the bottom brackets have a bracket bolt instead of a long slot. Lift up on the doors so that the bottom hinge pin comes out of the floor bracket, and pull the doors down from the top bracket.

Adjust the top brackets. Loosen the adjusting screw in the bracket, using a screwdriver, and slide the top bracket toward the center of the door opening if too much room exists between the lead door panels, or slide it toward the side jamb if the door panels press against each other. Tighten the adjusting screw.

Adjust the bottom brackets. Loosen the bracket bolt with an adjustable wrench, and slide the bracket in or out, as you did the top bracket. Tighten the bracket bolt.

Twist the bottom pivot pin on the doors clockwise, using the adjustable wrench, if you need to lower the door so that it's height and bottom edge matches the other one. Twist the pin counter-clockwise to raise the door height.

Hang the doors back up. Install the top pin into the top bracket, and press the roller atop the lead panel up into the track. Push the door up and insert the bottom pin into the floor bracket.

Slide the bi-fold doors closed. Measure the distance from the floor to the bottom door edges and the distance from the jambs to the outside door edges. Remove and adjust the doors again, as necessary, until they fit properly inside the uneven opening.