How to change a cylinder lock

Standard cylinder locks are also called night latch locks or Yale locks. They are fitted on the front door, which should also have a 5-lever mortice lock.

Both are easy to remove and replace with screwdrivers. Remember, you don't need to buy the whole lock set, just the cylinder.

1. Undo the screw on the lock body and remove it (keep the screws safe).
2. Undo the two long mounting plate screws.
3. Take out the old cylinder.
4. Put the new cylinder into the hole from the outside and secure it to the mounting plate from the inside of the door with the old connecting screws.