When your front door doesn't lock, you'll have to fix the problem quickly. Even if you have the most secure lock on the market, it's irrelevant when the latch doesn't even engage. Thankfully, the problem is usually easy to correct. Below, you'll find out how to tell what's causing your door to not lock and how to fix it.
Diagnosing the Source of the Problem
When your front door doesn't lock, the problem lies with either the door latch, the key, or the lock assembly. You can quickly find out which part is causing the problem with a simple test.
Open your door fully and attempt to lock the door with the key. If the latch fully extends and you're unable to push it back in, then the door latch is causing the problem. If you can't turn the key in the lock or if you're able to push the door latch back into the lock assembly, your issue is a faulty key or lock.
Once you've found out where the problem lies, read on to find out how to fix it.
Fixing a Misaligned Door Latch
When the door latch isn't aligned perfectly with the strike plate, it will be blocked from entering the door frame. Most commonly, this problem occurs when the door isn't perfectly squared with the door frame.
First, you should try tightening the hinges on the door. A loose screw in a door hinge can cause the door to become skewed in its frame, which will lead to the door latch becoming misaligned.
If tightening the hinges doesn't fix the problem, apply cornstarch to the door latch, close the door and then try to lock it. You'll be able to tell where the door latch is hitting the strike plate, since some of the cornstarch will be rubbed off. Once you know what part of the strike plate is blocking the door latch, you can widen the strike plate in that direction using a file. This will allow the door latch to enter into the door frame easily again.
Fixing a Problem With the Key or Lock
Although a misaligned door latch is a more common cause, sometimes a worn key or broken locking mechanism can cause the door to not lock. Keys wear down over time, and a worn key won't be able to engage the cylinders inside the lock. When a key becomes worn, you'll need to have another one cut in order to replace it. If you have another key that fits your front door, try using that one to lock it — if the key works, use it as the template to have another one cut.
In a similar way, dirt that gets inside the locking mechanism can cause the cylinders to become stuck. You can use canned air to blow dirt and dust out of the lock, allowing the cylinders to move freely again. If canned air doesn't work, the lock will need to be cleaned by a professional locksmith.
Finally, the cylinders inside the lock can wear down as well. The only solution to fix this problem is to replace the lock. Thankfully, this issue is fairly rare — locks are made to be very durable.
If you can't find the source of your problem or can't fix it on your own, call an emergency locksmith. A front door that doesn't lock is a significant security issue, since it allows burglars easy entry to your home. Emergency locksmith services can be dispatched quickly to repair the problem, restoring your safety and peace of mind.