Changing the locks should be the first thing you do when you move in. It’s simple, easy & inexpensive. Today I’m looking at UPVC doors (plastic & double glazed).
Unscrew the retaining screw
Start by opening the door with the key in it, then unscrewing the retaining screw. This can be found just under latch, level with the keyhole. The retaining screw is what holds the lock barrel in.
Remove the barrel
Gently pull the barrel out, using the key to twist. This will line up the internal latch with the rest of the lock, then you’ll be able to pull it out smoothly.
Measure the lock
Now the lock is out, you need two pieces of information in order to buy a new one. The brand will be clearly marked on it, & you also need to know the size. This comes in three parts; the two sides & the internal latch.
Put the new lock in
Now we basically just do the first part backwards. Put your new key into your new lock into your old door & wiggle it into place, making sure the internal latch is flush with the lock. I found that I had to loosen the handles a little by unscrewing them to be able to fully get my lock back in. Don’t take the key out yet!
Screw in the retaining screw
Screw the retaining screw back into place, & test the lock with your new key. Turn it a few times to make sure it’s secure & working.