A UPVC (unplasticized polyvinyl chloride) door lock is a rigid PVC lock used for its long-lasting and tough characteristics. UPVC locks are common in many homes and come in a variety of shapes, finishes and sizes. If your UPVC door lock got broken or you need to upgrade it for security, you may want to know how to change it. It is not necessary to hire a professional for this task because you can do it fairly easily.
Buy a new lock for your door of the same size as your old UPVC door lock.
Remove the old lock by unscrewing the bolt that holds it to the door with a flat head screwdriver.
Place the key into the lock and turn it to the side a little. When you feel that the key is firmly positioned in the lock, gently move it around a little bit to pull out the whole cylinder of the lock.
Put the new lock into the hole and tighten the lock bolt from the side. Be sure to place both the lock and the bolt in the right position.
Tightly screw the bolt of the new lock with a screwdriver. Close and open the door to check if everything is working as it should.