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General Advice

Replacing uPVC Door Locks

Replacing uPVC door and Aluminium door Euro Cylinders is quite straight forward. However there are a couple of things that you should be sure of. Firstly, be certain that you fit the correct size Euro Cylinder and secondly that your lock meets any requirements set down by your insurance company.

Fitting the correct size Euro Cylinder

It is vital that you order the correct size Euro Cylinder for your door. To determine which size you require, you must first remove the existing cylinder.

Removing existing cylinder

  1. Put your key in the lock and open the door.
  2. Remove the screw which is beneath the latch.
  3. Turn the key while apply slight pressure to the opposite end of the cylinder. As you do so the cam will line up with the rest of the lock and you will be able to slide the cylinder out towards yourself. The key usually needs to be turned approximately 25ยบ clockwise or anti-clockwise.

You can now measure the original cylinder.

Measuring the existing cylinder

On the side of the cylinder, under the cam, you will see a Fixing Hole. The size you require is determined by the distance from each edge of the cylinder to the centre of the fixing hole.

  1. Measure from the end of the cylinder to the centre of the Fixing Hole, to give the first measurement (a)
  2. Measure from the centre of the Fixing Hole to the other end of the cylinder, to give the second measurement (b)

If you intend to fit a standard double cylinder, which is keyed at both ends and you measured 35mm and 45mm, or 45mm and 35mm, then the size you should choose is 35/45.

This is the most common means of measuring a cylinder, however some manufacturers may adopt a different approach, therefore you should always confirm before placing an order.