So a mortice lock makes sense. Unless, that is, your door isn’t thick enough. To get a mortice lock into the door, you need a hole (the “mortice”). If your door is less than 44 mm thick, then the hole for, say, a Chubb lock weakens the door more than the lock strengthens the door.

(There’s another problem, of course: PVC doors are becoming more and more common, but insurance company personnel aren’t becoming any more intelligent. Many insurance policies don’t consider the completely different locking regime of PVC doors)

Thin doors often come about when Bodgit & Rakeitin carry out a conversion of a house into flats and fit internal quality doors for the flat doors.

What do you do if your insurance company insists that you weaken your front door? Change your insurance provider for one that isn’t exclusively populated by bean-counters and where there’s actually someone who is knowledgeable about security.

And if you’ve got a door that’s hovering around the 42 or 43 mm thickness and it already has a mortice lock, you have to ask yourself if it’s wise to add another mortice lock and put another big hole in it.

I mentioned elsewhere, a front door around where I live, fitted with three high security locks. Yesterday I came across a tiny, insubstantial shed door, where the same triplet of locks had been fitted, two of which were mortice locks!