Does the key turn in the lock but not unlock the door? Locks, latches, doorknobs, and hinges--door hardware--can make it difficult to get into or out of a door. But you can make it better by fixing that sticky lock or loose hinge.

How Does It Work?

A lock is a door fastener that is operated by a key or knob. A latch is a device that holds the door closed. A door knob releases a door latch. A hinge allows an attached door to swing. Together these devices open, close, and secure doors.

Exterior doors often have both a key-in-knob lock and a deadbolt or rim lock. Interior doors usually require only a door knob and latch. Both slide the latch into a strike plate mounted on the door jamb.

What Can Go Wrong?

Door accessories are relatively trouble free, but are used frequently, so problems can occur. Locks stick and work slowly. The key may break or may not open the door. The cylinder may move when the key turns. The key may turn but the bolt doesn't move. The bolt may not extend. Hinges may squeak, become loose or damaged. Keeping the door hardware clean and lubricated solves many potential problems.

Fix-It Tip

Want to save some money? If the door's lockset requires the service of a locksmith, remove it and take it in for service rather than pay for the locksmith to visit your home.

How Can I Identify the Problem?

If the key will not go into the lock on a very cold day, thaw the lock with a hair dryer or a deicing spray.

If a key breaks off in a lock, lift up the broken end with a straightened paper clip, then remove the stub with small pliers.

If a key won't easily slip in and out of the lock, have a new key made from one that isn't as worn. You also can lubricate the keyway with penetrating oil designed for locks or with graphite (never both).

If a key is difficult to turn and the key does not seem to be at fault, clean the lock and latch (see below). Also make sure the cylinder is properly aligned (see below).

If the cylinder moves when the key turns, tighten the screws that hold the cylinder in place.

If the key turns but the bolt doesn't move, follow the steps for fixing the bolt (see below).

If the bolt doesn't extend, check the alignment of the strike plate (see below).

If a push-button privacy lock gets activated, you typically can unlock it with a straightened paper clip pushed in to the small hole in the center of the knob.

If a door rubs all along the length of its latch edge, tighten any loose hinge screws.

If a door sticks or binds, check the hinges (see below).

If the hinges squeak, remove, clean, oil, and replace the hinge pins.

Fix-It Tip

If you remove a door from its hinges, reinstall the pins in the jamb hinge so you know where they are when it's time to replace the door.

What Parts, Materials, and Tools Do I Need?

Replacement hardware for household doors is available at hardware stores and home improvement centers. In fact, you'll probably find an entire section of door hardware. These are tools you'll need to fix or replace door hardware:

• Screwdrivers
• Wrenches
• Cleaning solvent
• Canned air
• Penetrating oil or graphite powder
• Small file

What Are the Steps to Fixing It?

Clean a lock assembly:

1. Remove the lock assembly from the door.
2. Soak the assembly with cleaning solvent, scrub it with a small brush, and dry it thoroughly with canned air.
3. Lubricate the components with penetrating oil.
4. Reassemble the lock assembly into the latch and reinstall it in the door.

Use a screwdriver to loosen the lock assembly, then remove it by hand.

1. Loosen the mounting screws that hold the cylinder on the door.
2. Insert the key in the cylinder, then move the cylinder so that the key's teeth face upward.
3. Retighten the mounting plate screws and remove the key.

To fix a bolt that doesn't move:

1. Make sure that the cylinder is aligned (see above).
2. Remove any debris or paint around the bolt and lubricate it with lightweight oil.
3. If necessary, disassemble the cylinder and bolt to check for loose or broken parts and repair or replace any problem pieces.

Realign a strike plate:

1. Unscrew the strike plate screws and remove the plate.
2. Trim the hole in the jamb as needed so the bolt enters the jamb hole.
3. Temporarily place the strike plate over the jamb hole and close the door to make sure the strike plate fits in the hole. Adjust as needed.
4. Hold the strike plate in place while closing the door to verify that the bolt fits through the strike plate and into the jamb hole.
5. Continue holding the strike plate in position and open the door. Mark and drill the strike plate holes, then install screws to hold it in place.

Tighten hinge screws:

1. Open the door and use a screwdriver to tighten the hinge screws.
2. If screws spin in place, use longer screws.
3. If longer screws still don't firmly attach the hinge, remove the hinge and fill the holes with wood filler or wood slivers. Allow filler to dry. Then reinstall the hinges with long screws.

Adjust the height of a hinge:

1. Remove the hinge from the jamb and/or door.
2. If the hinge is too shallow, use a chisel to remove excess wood. If the hinge is too deep, cut and insert a piece of solid (not corrugated) cardboard in the hinge mounting area.
3. Reinstall the hinge.

Fix-It Tip

Once a year, carefully remove hinge pins from door hinges and lubricate them with silicone grease or lubricating oil. Removing and reinstalling hinge pins will go much easier if you have a second person help you hold the door.