A bifold door is a type of sliding door. They are commonly used as closet doors or as dividers between rooms.
Bifold doors often become stuck when the tracks become filled with debris or when the doors are not correctly placed on the tracks.
Step 1 - Check Track Placement
The first step in correcting problems with a sticking bifold door is to determine whether the doors are correctly placed on their upper and lower tracks.
The doors will move awkwardly or may not move at all if they are off the tracks. If the doors are off the track, carefully lift them back into place back on the track.
You may need to take the doors down completely and adjust the wheels that are placed on the track, either by cleaning them or spraying them with mineral oil to make sure they are freely moving again.
You may also have to tap a bent track using a hammer, or otherwise realign the wheels.
Step 2 - Clean the Track
Another reason the door may stick is because the track is dirty or filled with debris. To fix this, push the doors all the way to the side so they are folded and the track is accessible.
Use a small brush or edge attachment on a vacuum to clean any debris out of the track. If dirt remains, spray a cleaner on the track and use a sponge to wipe it away.
Spray the track with mineral oil or WD40 so the wheels and door will slide smoothly. Move the door back and forth several times to evenly distribute the lubricant along the track.
Step 3 - Consider Other Problems
Bifold doors are constructed with two panels that are held together by hinges, and these can occasionally cause the doors to stick.
If the panels are sticking when the doors are opened and closed, carefully spray some mineral oil or WD40 along the hinges and work the doors open and closed several times.
Wipe any excess lubricant away from the panels.
Hinges can also become clogged with debris. It may be helpful to clean the hinges occasionally to remove any accumulated dust or dirt from the hinges and keep them in good working condition.