How to tune up a sliding door

If the wheels or tracks themselves are worn, they’ll need replacement or repair. In either case, remove the door from its jamb. The top of the door is held in its track by “stop” moulding (2) on the interior side or, in older doors, a U-shaped channel. Use the adjustment screws to lower the door on its wheels as much as possible. If there’s stop moulding, unscrew it. If it’s painted or varnished, use a utility knife to score the joint between the moulding and the door frame to prevent chipping when you remove the moulding. Then, with a helper, carefully tilt the door back into the room and lift it off the lower track. In the case of a door with a U-channel, lift the door just high enough in the channel to pull the bottom out of its track. Glass doors are very heavy, so never leave them standing unsecured.

Remove the wheel cartridges from the bottom of the door (next page). Cleaning and lubricating may get them rolling again, but if the wheels or bearings are worn, you’ll need replacements. Start at a hardware store or big-box home centre, which will likely carry generic wheel cartridges. Another good option is a glass repair shop, which may have more selection. If you have to reinstall the door in order to go shopping, snap a photo of the cartridges and note their dimensions, as well as any model numbers or other manufacturers’ marks.