Plastic doors and exit sensors for burglar alarms

[Spoon]

I am not sure if there is any metal reinforcing in the door which could present a problem in drilling it to take the magnet. The door is the final exit door and needs a contact to allow the setting of the alarm.

Thanks for all replies.

Someone please correct me if I'm wrong, but doesn't the alarm just require a Normally Closed signal from a device, like a magnet, for the exit?
It's been a bit since I messed with alarms.
If the above it true then you could use the setup that @DPG has mentioned above and use the NC contact of a PIR.

 

[Tafia43]

Good call. I'll have to do that. Now I just need to find the route of the alarm cable and dig it out of the plaster.

Thanks to all for replies. Much appreciated.