Do I need a double glazing person to fix my door – No. your double glazed door has a lock in it. It needs a locksmith, a locksmith that is confident with UPVC door. UPVC doors are made up with a muli-point locking mechanism which are then held in place wit a lock cylinder. It is important that the locking points fit correctly into the keeps otherwise this stresses the gearbox, which then breaks. A locksmith will also advise you if the locking mechanism has enough locking points and if the lock cylinder which holds it all in place has any security. Please see video.
What would my insurance company like to see – Insurance companies usually ask for a British Standard 5 lever deadlock on wooden doors. These can be identified by the faceplate of the lock, it should have the BS kitemark see image
On UPVC and aluminium doors your insurance company would usually be looking for 2 or three locking points, however they do not request any specific lock cylinder and this is what hold the locking mechanism in place, even if the door is brand new sometimes the double glazing company will only put a shinny £2.50 lock to hold it in place. Please see video.
All windows with the acceptation of escape windows should be lockable.
Should I change my locks when I buy a new house? YES, in my eyes this should be a requirement of your insurance, you have no idea who has a key, whether one was left with a neighbour, ex-partner, decorator or even left under a brick? I’ve had customers book me up to change the locks when they move in only to cancel because the locks looked shinny and new!