The door opening in the framing is not square.
How to fix a gap in a sliding glass door.
First locate the roller adjustment screws and use a screwdriver to turn the screws counterclockwise.
Buy new foam filled vinyl tube weatherstripping the press it.
The proper way to fix it would be to remove the door and door frame and square up the opening in the house framing.
Gap between sliding doors doors cannot close properly.
For the best seal my recommendation would be some pieces of weatherstripping or gasket.
Pry out the old weatherstripping from inside the door frame using a flat head screwdriver.
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Sliding glass door adjustments.
Then remove the door stop at the top of the frame which should be as simple as unscrewing it.
Remove the door from the track.
It looks like the gap is caused by the hardware for this barn style door which is a common scenario.
Push in the weatherstripping until secure.
This will retract the rollers and make the door flush with the track.
This video shows you how to take apart sliding glass doors.
Simonton windows doors 102 622 views.
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