Fix a Sticking Door Before You Reach for the Plane

Close the door until it just barely touches, then slide a dollar bill into the gap and drag it all the way around the perimeter. Where the bill grabs, that's your rub. Where it slides free, leave it alone. Total cost of this diagnostic: zero, assuming you have a dollar.

Most people skip this and go straight to sanding. Then they've got a door that closes fine in August and rattles in its frame come February, because they removed wood that was never the problem.

Do the bill test on a dry day and a damp one if you can. A door that sticks only after three days of rain is a different animal than one that's been dragging since Easter.

Read the rub, because it tells you what's wrong

Rubbing at the top of the latch side. That's the classic. The door has sagged and the top corner is swinging into the jamb. Cause is almost always the top hinge pulling loose from the stud. Fix takes ten minutes.

Rubbing at the bottom of the latch side, gap opening at the top. The hinge side is being pushed out, or the door is hitting a high spot in the flooring. New carpet and thick LVP are frequent offenders.

Dragging on the hinge side itself. Hinge is mortised too deep or a screw head is standing proud. Look for a screw that isn't sitting flush in its countersink.

Tight all the way around, evenly. Now you're talking about swelling, and that's a moisture conversation.

Closes fine but won't latch, or you have to lift it. Strike plate problem. The latch bolt and the hole aren't lining up. That's a separate fix and it's the easiest one on the list.

Before you drive a long screw, kill the breaker

Here's the part nobody mentions. The light switch for that room is usually mounted in a box nailed to the stud right beside the door, on the latch side, about 48 inches up. The wiring runs through that stud bay.

If you're driving three-inch screws through a jamb, or prying casing off to shim, throw the breaker for that room first and confirm the lights are dead. It takes twenty seconds. A screw through a hot conductor takes considerably longer to deal with.

Safety glasses when you chisel. Doors are heavy and awkward. If you pull a door off its hinges, have somebody hold it or lean it against a wall with a towel under the edge so it doesn't skate.

Fix one: the long screw trick

Open the door about 30 degrees and slip a shim or a folded towel under the latch-side corner to take the weight off the hinges. A cedar shim bundle is a few bucks at any home center and you'll use them for the rest of your life.

Go to the top hinge, the one on the jamb side. Remove the middle screw. Almost every builder installs the hinge with three-quarter-inch screws that bite into nothing but the jamb board, which is three-quarters of an inch thick. That screw isn't holding anything.

Replace it with a #9 by 3-inch wood screw. A small box runs under ten dollars. Drill a pilot hole first, straight in, and drive it until it's snug and flush. Not gorilla tight. You'll crush the jamb and pull it toward the stud too far, and then you've traded one problem for another.

Do the same on the second screw if the first one didn't close the gap. Pull the towel, swing the door, run the dollar bill again.

That's it. That's the fix for most sagging doors in America.

Fix two: shim the hinge the other direction

Sometimes the door needs to move away from the hinge side, not toward it. Classic sign: the latch-side gap is tight at the bottom and wide at the top.

Unscrew the bottom hinge leaf from the jamb. Cut a piece of thin cardboard, a cereal box works, to the shape of the hinge leaf. Cut notches so it fits around the screw holes rather than trying to poke the screws through. Slide it in behind the leaf and screw the hinge back down.

One layer of cereal box moves the door surprisingly far. Two is usually too many. Test between each layer.

You can also go the opposite way: if a hinge is mortised too deep and the door binds on the hinge side, deepen the other hinges' mortises slightly with a sharp one-inch chisel. A decent chisel is in the fifteen-to-thirty-dollar range and you want it sharp enough to shave a pencil, not the dull one in the junk drawer.

Fix three: the strike plate

Rub a little lipstick or a carpenter's pencil on the end of the latch bolt, close the door, and look at the mark on the strike plate. Now you know exactly which way it's off.

Off by less than an eighth of an inch? Take a flat bastard file, ten bucks or so, and open the strike plate hole in the direction you need. Three or four minutes of filing. You'll want to file the hole in the metal plate and also chisel the wood behind it, because the latch needs somewhere to go.

Off by more than an eighth? Move the plate. Unscrew it, squirt wood glue into the old screw holes, tap in golf tees or a glued dowel, let it cure overnight, cut flush, then re-drill in the new spot. Toothpicks work in a pinch but a golf tee is stronger and costs about a quarter.

Fix four: swelling, and why you should wait

A door that's tight everywhere in July and fine in November isn't a door problem. It's a humidity problem, and planing it in July guarantees a drafty gap in January.

Get the moisture down first. A dehumidifier in the basement, a bath fan that actually vents outside, gutters that aren't dumping against the foundation. Exterior doors that swell usually have bare or cracked paint on the top and bottom edges, which is where water climbs in. Pull the door, hit those edges with a coat of primer and paint, and you've sealed the sponge.

If it still binds at the driest point of the year, then you plane. A block plane runs thirty to fifty dollars and gives you more control than a belt sander, which will gouge a door in about two seconds of inattention. Mark your line in pencil, take off shavings, not chunks, and prime the cut edge the same day.

Never plane the hinge side. Take it off the latch side and re-bevel slightly so the leading edge clears.

When it's not the door

If the gap is wedge-shaped and the drywall above the door has a crack running diagonally from the corner, the opening is out of square. That's the house moving, not the door. Same story if two or three doors on the same wall all went bad in the same season, or the floor has a noticeable slope.

Get a licensed contractor or a structural engineer to look at it before you chisel anything. You can make a racked door close by cutting it to match a crooked opening, but you've just hidden the evidence.

Two other pro calls. If it's the door between an attached garage and the house, or a unit entry door in a condo or apartment building, it may be fire-rated. Trimming it, drilling it, or pulling the self-closing hinges can void the rating and put you crossways with code. Requirements vary by jurisdiction, so ask your local building department before you touch it.

And if a steel exterior door is dragging, adjust the threshold screws before you touch the slab. They're usually four or five Phillips heads hidden under the sweep, and turning them raises or lowers the whole sill.

Run the dollar bill one more time when you're done. If it slides clean around the whole frame, put the tools away and go enjoy a door that shuts with one hand and a coffee in the other.