Why a door sticks, drags or will not latch
Every door repair starts with the gap around the door. That reveal should run even, roughly 3 mm (1/8 in) at the top and the sides, with a little more at the floor. When the gap closes up at the top of the latch side and opens at the bottom, the door is sagging on its hinges. A door that swings open or shut on its own is telling you the hinge jamb is out of plumb.
Season and age do the rest. Solid wood swells through a humid Toronto July and shrinks again in February, so a door that catches only in summer usually needs hinge work rather than a plane. Houses settle, floors get new covering, and paint builds up in a hinge mortise until the door sits proud of where it started.
Door repair before door replacement
My first check in any door repair is the top hinge. The short screws that hold a hinge to a jamb bite only into thin jamb stock, and over the years they work loose and let the door drop. Swapping two of them for 75 mm (3 in) screws that pass through the jamb and the shims into the framing behind, then drawing them up gradually, pulls the top of the door back and lifts the latch corner. That one repair sorts out a large share of dragging doors.
Stripped screw holes get glued hardwood plugs and are re-drilled, which holds far better than driving a fatter screw into a chewed-out hole. A latch that misses is diagnosed before any metal comes off: a cardboard shim behind a hinge leaf moves the door within the opening, and a strike plate that has to shift more than a hair gets its old mortise filled and a fresh one cut rather than filed into a slot. Planing is the last resort, and a planed edge always gets sealed so it does not soak up moisture.
Hanging a new door: slab or pre-hung
Pre-hung units go in faster and end up straighter, so they are my first suggestion when a jamb is damaged. The hinge jamb is set plumb in both directions and shimmed behind every hinge, fasteners go through the shims so the jamb cannot bow, and the reveal is checked top to bottom before the casing goes on.
- Interior doors adjusted, rehung or replaced
- Hinges, mortises and stripped screw holes repaired
- Strike plates realigned so latches catch cleanly
- Slab doors mortised for hinges and bored for hardware
- Doors undercut for new flooring or a thicker rug
Reusing a sound jamb means fitting a slab instead. Hinge positions transfer from the old door, mortises are cut to the exact depth of the leaf so the door neither binds nor gaps, and the hardware is bored at the correct backset, either 60 mm (2 3/8 in) or 70 mm (2 3/4 in). Cutting a brand new opening into a wall is another matter, since it means framing and possible structural work, and that goes to a licensed contractor.
Sliding, bifold and patio doors
Closet doors get more use than any other door in a house and the least maintenance. Bifolds hang from a top pivot in an adjustable bracket and turn on a bottom pivot, and both can be shifted until the panels line up and close flat. Sliding closet doors depend on their rollers, a straight track and the floor guide that everyone loses during a move.
Patio doors are heavier and far less forgiving. A door that scrapes usually has flat-spotted rollers and a track full of grit, and both need dealing with together, since new rollers in a dirty track wear out quickly. Rollers are changed in pairs, the adjustment screws behind the plugs at the bottom of the stiles reset the height, and the track gets a dry lubricant instead of oil, which only collects dirt.
Drafts, sweeps and weather stripping
Exterior doors leak air in three places: the sides and head, the bottom, and the corners where the two meet. Kerf-in weather stripping pushes into the groove in the jamb and is quick to replace once the right profile is identified. A worn door sweep is easy to change, and an adjustable threshold has screws along its top that raise the seal until daylight disappears under the closed door.
Test it yourself before you call. Close the door on a sheet of paper and pull. If the paper slides out with no drag at all, the seal is not touching at that point. Do the same at the top corners and the latch side, mark what fails, and door repair on that draft becomes a short visit rather than guesswork.