Having spoken to a few people, i have had varying responses when i pose the question how do i hang and internal door? does someone out there have an definitive answer pls?
As a chippy, I would say it's easy. However I do it regularly, so I would. It is not beyond the scope of the average handyman, with a sharp plane, chisel, and drill.
However, depending on what sort (weight) of door you are planning to fit, and what state the frame is in, you may be better to get a local chippy in.
B & Q used to do leaflets on how to do it, if not I think Wickes do leaflets.
In a nutshell, make it fit. Plane equally off both sides. Take equal off top and bottom, but bottom rail generally wider, so If you only have a small amount to come off height, do it all on bottom.
Stick a 2p coin on the top, and lever it up into place in the frame. Then come 7" down, and mark your hinge on door and frame. Do the same 9" up. Cut hinge slots out with a sharp chisel. Use 3" hinges for a normal door. Drill pilot holes in door and frame, fit hinges using 1and a quarter no 8 screws to door.
Lever it up into place, and screw to frame. Fit lock/ latch, and clean up.
Hope this helps