Q. A couple of the wood doors in our house stick and are hard to open and close. I tried tightening the hinge screws, but it didn’t help. What next?
A. Doors sometimes stick because the wood swells during periods of high humidity. If this is seasonal in your area, the wood will probably shrink when drier weather comes and the problem will solve itself. But there are other causes, such as out-of-square door frames, and you’ll need to do some detective work to find the sticking point.
Tightening the hinge screws, and making sure they are gripping firmly, is always the best first step. Next, close the door as tightly as possible and see if you can insert the blade of a putty knife between the vertical edge of the door and the frame on the lock side. If the blade jams at some point on that edge, mark the spot with a piece of tape and open the door. Sand the jamming area with 100-grit sandpaper on a sanding block; try to remove only a thin layer of paint or finish, which is often enough.
Removing wood from the door is a last resort, but if the lock edge is still jamming and there is no other option, use a small block plane to remove thin shavings; this can often be done without removing the door from the hinges. If the jamming point isn’t on the lock edge, the top corner on the lock side and the bottom corner on that side are other common sticking points. Either of these jams can usually be cured with shims, as long as you have that small gap on the lock side.
Shims are simply thin pieces of cardboard that fit behind one of the hinge leafs. Cardboard cut from the back of a writing tablet or old playing cards make good shims. The point of a shim is to tilt the door just a tiny bit to relieve that jam on the top corner or bottom corner.
To cure a top-corner jam, shim the top hinge leaf where the door is attached to the frame. For a bottom-corner jam, shim the bottom hinge leaf. To insert a shim, open the door as far as possible, and put a wedge or other support under the door bottom to hold it in position. Cut the shim so it will fit in the hinge mortise, and punch screw holes in it with an awl or ice pick. Remove the screws from the hinge leaf, put the shim behind it, and screw the hinge leaf back on tightly.
A couple of shims might be needed in some cases, which is OK as long as the door isn’t tilted enough to jam at the lock edge.