Frameless glass shower doors can hang from an overhead track or from side hinges. Since they do not have a frame, the track or hinges are attached directly to the glass or at least appear to be. Actually, the hardware usually clamps the door when you tighten the screws, and a rubber gasket between the hardware and the door prevents damage to the glass. When the screws become loose, the door can slip out and sag or hang unevenly. Readjust these doors with a screwdriver and a piece of wood to prop the door.
Adjusting Hanging Sliding Doors
Step 1: Remove Door From Its Track
Remove the sliding glass door from the track by swinging the bottom toward the back of the shower and then lifting the door until the wheels at the top are free of the track. Lift the door away from the track and set it down on a flat surface.
Step 2: Loosen and Adjust Attachment Plates
Loosen the screws holding the sliding wheels to the top of the door with a screwdriver until you can slide the attachment plates freely. Adjust the plates so that the metal at the top of the plate is seated against the top of the glass. Tighten the screws.
Step 3: Rehang the Door
Rehang the door by going inside the tub or shower and lifting the door until it touches the top of the metal frame over the track. Angle the door so that the bottom is away from the door frame and hook the wheels into the track. Let the door swing gently into the frame.
Adjusting Pivot Shower Doors
Step 1: Wedge the Door Open
Open the shower door and wedge a piece of wood under the corner.
Step 2: Unscrew the Hinges
Unscrew the hinges from the shower wall, starting with the bottom hinge. As you loosen the top hinge, the door will start to fall away from the wall, so hold it steady while you finish unscrewing it.
Step 3: Seat the Hinges
Set the door on its edge on a bath mat or towel with the hinges facing you. Loosen the screws holding the hinges and slide the hinges until they are seated on the edge of the door, then tighten the screws. Some doors have a piano hinge with a clamp that extends the length of the door. Make sure the top of this hinge is flush with the top of the door and that the entire hinge is seated against the edge of the glass before you tighten the screws.
Step 4: Position the Door
Set the door on the wood and move it into position so that the hinges are over the holes in the wall of the shower, then screw the hinges into the wall.
Sometimes the doors are slipping because the rubber gaskets are failing. If this is the case, remove the gaskets, spread a little silicone caulk on the parts that contact the glass and replace them.
Glass shower doors are heavy and breakable. Have a friend help you if you do not feel confident in your ability to safely lift one.
Chris Deziel is a contractor, builder and general fix-it pro who has been active in the construction trades for 40 years. He has degrees in science and humanities and years of teaching experience. An avid craftsman and musician, Deziel began writing on home improvement topics in 2010. He worked as an expert consultant with eHow Now and Pro Referral -- a Home Depot site. A DIYer by nature, Deziel regularly shares tips and tricks for a better home and garden at Hunker.com.