Ok I will be starting to build partition wall, but how do I allow for
the door side of things.
Example
I have the partition wall built with uprights and battens in place.
I would then fix the plasterboard. So for the sake of arguement I am
using 80mm x 50mm timber and 10mm thick plasterboard (for easy calculation)
The final partition would therefore be 100mm thick.

Do I now just line the interior of the door frame with 100mm and say
20mm thick piece of wood allowing for say 6mm clearance for fitting door.