Re: The Bruce Willis film RED
They may go all the way up on the wall the door is on for more rigidity, but not all the way on an adjoining room that you can get into. When a company moves into the space, all they might do is fit a locking door handle to use the room for something restricted rather than properly secure it.
With drop down ceilings, another thing to look for is security device wiring that's beanie'd in at the top of the wall or at least accessible so it can be bypassed. If you know the brand of the alarm system, it's easy to look up if door sensors are N.O. or N.C. as a default. A tricky installer would configure the system to do it both ways so anybody that bypasses one may set off the next one. If you can see the connections to the reed switch, you will be able to tell which way you need to go with a bypass.