I am writing this piece in light of a recent job I attended. I travelled around 40 minutes to a job which was a problem with a double glazed door that was not locking. When I got there, I had fixed the problem before the customer finished explaining it to me. All that had happened was that a screw had come loose, and the part that the latch goes into on the door frame was at a slight angle, meaning the latch was going out all the way when the door was closed. In some upvc door mechanisms, this stops the door from locking. It took seconds to fix. Because I was sub-contracting to a national company, the customer had to pay the full cost, which with VAT was over £100.

So, I decided to put together a little check list and fix it yourself solution piece so you can save yourself some money if your mechanism goes wrong:

Fix your locks

• The first thing to check is that your locking mechanism works. This is the easy bit. Open the door and lift the handles. Turn the key to lock it. If all goes smoothly, then the problem is not with the mechanism. Repeat this a few times to be sure. If it is hard to lift the handles or the key does not turn easily, look to see if there is any sign of rust or dirt build up, especially near the bottom. If so, then give it a clean, squirt some oil into every part you can and try again. If you are still having problems at this point, call a locksmith.
• Supposing the mechanism is working fine, your next task is to check the door has not dropped, or warped in sunlight. With the handles pulled down, slowly close the door. You will see and feel if the door is rubbing against the frame anywhere. If it is, then it is possible that you can adjust the door. Most modern upvc door have hinges that can be adjusted. Look for small plastic caps on the hinges. If you remove these, they should reveal a place to insert an allen key. Turn the key one half turn in one direction with the door open. You should see door move one way or the other slightly. Try to close the door. If it catches more, turn the allen key back to its original position and then another half turn the other way. This should make it easier. Repeat this process until the door closes without rubbing against the door frame. Remember, if you are moving the bottom of the door one way, you may need to move the top of the door the other way to make it straight. And only do half turns each time. This can be a tricky process, so unless you feel confident, call a locksmith to do this for you. On older upvc doors that are pinned through the hinges, you might notice that the hinges are bent. This is a job for the professional – possibly a upvc repair engineer would be your best bet, although some locksmiths do undertake this work as well.
• So now we have a door that closes without catching on the frame, but still will not lock. In most cases, there is something to adjust. If the door has sliding rollers, you will see they have slots for allen keys. You can rotate these to make a slight difference. Only turn a quarter turn before testing to see if it makes a difference and do this for the complete circle to find out which position is best.
• For hooks, bolts and latches, the adjustment is with the keeps on the door frame itself. There is usually something you can turn with either a screw driver or allen to help the moving part of the mechanism fit better. Here it is trial and error until you get the feel of what helps where.
• If the door is still not locking after you have fiddled and adjusted, always taking note of original positions, it might be time to get creative. This is the point where you need to remove the keeps from the door frame, one by one to see which one is causing the problem. Every time you take one off, try the door until it locks. If your luck is like mine sometimes, you will them all off before you find the culprit. Replacing the offending keep a few millimetres lower usually solves the problem. Put the remaining keeps back one at a time and test the door with each replacement just in case one or more of the others is also causing a problem.

If none of these measures rectifies your problem, or you are not comfortable with carrying out the tasks, then call your local locksmith. There are still things that could potentially be causing the problem, but hopefully by the time you get to this, you will know you have done all you can to save yourself paying out money needlessly.

If you have any questions regarding the above, please get in touch via any of the methods on my contacts page.

Thanks for reading.