UPVC doors are usually fitted with a locking system that comprises a “multi point locking system” and a key cylinder.
The multi point locking as the name suggests means that when the UPVC door locks are in the locked position there are a number points around the doors edge that engage to secure the door in place. These locking points are located on a metal strip on the leading edge of the door.
There are usually six locking points on this metal strip and include a combination of roller cams (2 No), hook bolts (2 No), dead bolt (1 No) and a door latch. The latch is used to keep the door in the closed position but not locked. Each of these points engages with metal keepers fixed to the main door frame.
To engage the multi point locking system on the PVC front doors, pull the door lever handle upwards. All six points are now engaged and in the locked position. To complete the locking process, turn the cylinder, using the key, once or twice (depending on the cylinder type) and the door is now secure.
Some multi points do not require the lifting of the handle to engage the locking point. In this case you just turn the key cylinder and the door is locked.
With these locking systems the weakest point is the cylinder since this is the only part of the device that is exposed. If an attacker can bypass the cylinder, then access to the multi point system is feasible and the door can be opened.
It is therefore important to choose the cylinder wisely for front doors or any door. A popular cylinder fitted to a uPVC front door is the EURO profile cylinder. There have been problems with these types of cylinders in the past. Burglars have been able to bypass them in seconds by basically breaking or snapping the end of the cylinder with simple tools, giving access to the multi point and opening the door.
Newer versions of these Euro cylinders have been developed so that if the end is snapped off, enough of the cylinder will remain in place and not expose the inner working of the lock. Be sure you have the newer version fitted when ordering new doors.