How to fix a door that sticks at the top

The personality of an old door changes with the seasons. Pulled tight in winter, it's a stalwart guardian against chills and drafts. But by August, heat has driven moisture deep into the grain, and the once-yielding door has become swollen and stuck.

This Old House general contractor Tom Silva confronts a stubborn summertime door with a jack plane and a little restraint. "You want to take off the minimum amount of wood necessary because the door is going to shrink again in the winter," says Tom. "If you remove too much, it will sit loose in the opening." Follow along as Tom fixes a swelled door in his own home with just a few simple tools.

Close Shave

Tom's rule of thumb for keeping a door from sticking in the jamb is that the reveal—the space between the door and jamb—should be 1/8 to 3/16 inch wide, or about the thickness of a nickel.

Examining one sticky bedroom door in his house, Tom spends a little time getting a sense of its predicament. He opens and closes it to see where it catches, and he eyeballs the reveal. An uneven reveal may mean the hinges are loose or out of alignment. And, in fact, the screws holding the top hinge to the jamb have stripped their holes, causing the door to sag. But after fixing them, Tom finds that the door still sticks. Satisfied that humidity is the culprit, he pulls the hinge pins, lifts the door from the jamb, and gets ready to plane.

Check for a Loose Hinge

To repair a stripped screw hole under the hinge leaf, Tom plugs the hole and gives the screw something new to bite into. He whittles a ¼-inch-wide, slightly tapered splinter out of a scrap of wood, then squeezes wood glue onto it and into the screw hole. He taps in the plug with his hammer, and glue oozes out of the hole. "You don't want to have a dry spot," Tom says, as he wipes away the excess, "or you won't get good adhesion." He snaps the protruding sliver flush with the hinge leaf. With the glue still wet, he refastens the hardware, cinching the screw tight.

Deepen the Hinge Mortises

After repairing the hinge, Tom sees that the door is still too big to close smoothly; he has no choice but to plane it to fit. To avoid disassembling the doorknob, he'll take the excess off the hinge side.

First he removes the hinges so he can chisel their mortises ⅛ inch deeper—the same amount he will plane from the door's edge. Holding a ¾-inch chisel vertically in the mortise, he hammers a dozen or so parallel ⅛-inch-deep cuts across the width of the mortise and one long cut against its inside edge. Then he leans his weight on the chisel—bevel side up—and rocks it gently back and forth, plowing out the chips of wood. He repeats the process on the other mortise.

Plane the Door

Tom knows that cutting through the layers of paint on this old door means he'll likely have to sharpen the plane's blade, called an iron, when the job is done. Luckily the finish is lead free, so slicing through it will not send hazardous particles flying. "If it were lead paint, I'd first want to use a chemical stripper," he says.

Curls of pine tumble to the floor as he runs the plane at a slight angle in long, smooth strokes along the length of the door. The plane iron leaves the edges sharp, so Tom rounds them slightly with some sandpaper to help them better accept paint.

Paint the Raw Wood

Before he goes any further, Tom slides each hinge leaf into its mortise to make sure the metal is flush with the door's edge. Then he pops the hinges back out and reaches for his paintbrush. "It's important to get the wood primed and painted as soon as possible," Tom says, to slow the creep of moisture. Otherwise, the door will swell again almost immediately, and "you'll be right back where you started." He brushes on a primer coat, then a finish coat, carefully blending the new paint into the old without dripping down the face of the door.

Rehang the door

Once the paint has dried, Tom re­attaches the hinge leaves. Then he hoists the door back into its opening, lining up the knuckles and dropping in the pins—first top, then bottom. Using the handle of his screwdriver, Tom taps each pin home, and then gives the door a test swing. It obligingly snaps shut, and the latch clicks cleanly into its strike plate. When Tom turns the doorknob and gives a gentle tug, it opens without resistance.