Door Lock Sticking or Won't Turn? Common Causes and Fixes

If your key is hard to turn or the deadbolt won't throw all the way, it's usually one of four things: a dirty or worn cylinder, a worn-down key, a strike plate that's drifted out of line, or a door that's swollen from moisture. Try the key alone first, without pushing or pulling on the door. If it still binds, the problem is inside the lock. If it only sticks when the door is shut, the problem is the door or frame.

Is it the key or the lock?

Grab a spare key if you have one and try it. If the spare turns smoothly and your everyday key doesn't, the key is worn, not the lock. House keys wear down faster than people expect, especially brass keys cut years ago. The ridges round off, the key stops seating the pins properly, and you get that gritty half-turn feeling.

If every key you own sticks in the same lock, the cylinder itself is the problem. That's a different fix, and it usually doesn't involve replacing the whole lock.

Door lock sticking from a dirty or worn cylinder

Dust, old grease, and salt air off the water work their way into a lock cylinder over years. Combined with worn pins, this gives you that gritty, inconsistent turn where some days the key works fine and other days it won't budge.

• Don't use WD-40. It feels like it helps for a day, then it attracts dust and dries into a gum that makes the problem worse within a few weeks.
• Use a dry lubricant instead. Powdered graphite or a Teflon-based lock lubricant, a few puffs into the keyway, then work the key in and out a dozen times.
• Don't force a stubborn key. Keys snap off in cylinders more often from forcing a half-turn than from anything else. A broken key in the lock usually means drilling or picking it out, which costs more than a service call would have.

A cylinder clean and lubrication job typically takes 15 to 30 minutes on site, with a typical range of $90 to $140 depending on the lock brand and how worn the pins are.

Strike plate and door alignment problems

This is the most common cause on older Vancouver houses, especially wood-frame homes in Kitsilano, Mount Pleasant, and the east side where doors have settled over 60 or 80 years. The deadbolt or latch lines up fine when the door is open, but the moment you shut it, the bolt hits the edge of the strike plate instead of sliding into it.

You'll feel this as the key turning partway, then stopping hard. It's not the lock failing, it's the bolt meeting metal instead of the hole. A locksmith checks this by removing the strike plate and looking at where the bolt actually contacts it, then either re-cutting the mortise, shimming the hinges, or moving the plate a few millimetres. This is usually a 30 to 45 minute job, typical range $100 to $180, and it's a permanent fix rather than something that needs redoing every season.

Deadbolt won't throw: alignment vs worn parts

If the key turns but the bolt doesn't extend, or it extends partway and jams, check whether the door is sagging. Open the door and look at the gap along the top and the latch side. An uneven gap, wider at the top than the bottom, usually means the hinges have loosened or the door has dropped slightly on its frame.

Tightening hinge screws is a five-minute fix that solves this more often than people expect. If the screw holes have worn out (common on original 1970s and 80s hollow-core interior doors), longer screws or a wood filler and re-drill job fixes it properly. If tightening the hinges doesn't help, the deadbolt's internal bolt mechanism may be worn, which usually points toward replacement rather than repair.

Weather, humidity and seasonal swelling

Vancouver's wet winters swell wood doors and frames, and it's common for a lock that worked fine in August to start sticking in November. If your door only sticks a few months of the year and loosens up again in summer, that's moisture, not a failing lock. Planing a small amount off the door edge, usually a job for a carpenter rather than a locksmith, fixes this permanently. A locksmith can still adjust the strike plate to compensate in the meantime.

Exterior metal doors and sliding doors behave differently. If you're dealing with a sliding balcony or patio door that won't latch, that's usually a track and roller issue rather than a cylinder problem. We've covered that separately in our guide to sliding balcony door lock repair.

When to replace the lock instead of fixing it

• The lock is original to a house built before the 1990s. Parts wear out, and pin tumbler cylinders that old have usually had thousands of turns. Repair sometimes just buys you a few more months.
• You've had it picked or drilled before. A cylinder that's been compromised once is weaker at the pins and more likely to keep sticking.
• You want all your doors on one key. If you're replacing one lock anyway, rekeying the rest to match is usually a small add-on cost rather than a second full job.

Replacing a single deadbolt typically runs $150 to $280 installed, grade-dependent, and takes 20 to 30 minutes per door. A basic grade 2 residential deadbolt is fine for most interior and secondary doors; a grade 1 is worth the extra cost on your main entry door.

Get it looked at before it fails completely

If your key is sticking but still turning, you've got time to book a service call rather than deal with an emergency lockout. Have the lock brand on hand if you know it, and let us know whether it's the key, the cylinder, or the door that seems to be the problem; that helps us bring the right parts the first time. Call The Vancouver Locksmith Ltd. at +17786551957, or read more about how we work on our about page.

Frequently asked questions

Why does my key work in the morning but not at night?

That's almost always temperature or humidity related. Wood doors expand slightly as moisture and temperature shift through the day, changing how the bolt lines up with the strike plate.

Is it safe to spray oil into a sticking lock?

Household oil and WD-40 aren't a good long-term fix. They loosen things up briefly, then collect dust and grit inside the cylinder, which makes the stick worse within weeks. A dry graphite or Teflon lubricant is the better option.

My key is stuck halfway in the lock. What now?

Stop turning and don't pull hard on it. Forcing it is the most common way keys snap inside a cylinder, and a broken key usually means the lock has to be drilled or picked open, which costs more than a straightforward service call.