How do I replace a suspended ceiling in basement flat?

[nrglux]

Hi,
I am after instructions on how to replace a suspended ceiling in a basement flat (square panel type found in offices) I would like to remove all the tin frame work holding the suspended ceiling and nail plasterboard directly onto the joists. I'm guessing the suspended ceiling was put in as it was cheaper than making a level ceiling with plasterboard. I think there is old fibre board currently nailed to the joists behind the suspended ceiling. There is not a great deal of height so I wanted to avoid constructing a level frame for the plasterboard just below the existing joists. Is there a way of leveling old joists (eg by adding wood to underside) to make level for plasterboard?
Thanks

 

[Symptoms]

glux - first strip off all the stuff covering the underside of the joists (wear goggles 'cos there is likely to be a ton of crap up there ready to fall into your eyes). Next get a long straight-edge, straight bit of timber will do, and use this to check the flatness of the joists - my bet is they'll be OK. It is possible to fix plasterboard on your own, but if you do so make a 'dead man' or 'dead man's hand' (like a giant tee-square - the short cross piece goes across the board and the long bit acts as a leg on the floor) to support the board; you could get a pair of Boardmates for about £20 which act like a second set of hands - great bits of kit for doing this type of job. It's better to be 2 or 3 handed if you're a novice. Don't use nails to fix, always use plasterboard screws.

 

[nrglux]

" Next get a long straight-edge, straight bit of timber will do, and use this to check the flatness of the joists - my bet is they'll be OK."
Thanks for the reply Symptoms. Can anyone offer suggestions on what to do if I find the straight egde rocks considerably?

 

[Symptoms]

glux - you'll have to 'shim' the gaps at the screw positions. Unless you are going to use a wallboard adhesive (something like Gripfil) all along the joist/plasterboard interface, you only have to shim where the screws penetrate. Shims to use are 2 (very, very thin) opposing wooden wedges; as they are pushed together the height increases to bridge the gap, also by using 2 opposing wedges the faces remain parallel, one wedge and the face will be at an angle - not good when nipping up the p/board with screws. Obviously you do this at the straight-edge stage and pin the shims in positon until you sheet-up & screw (through the shims).

 

[nrglux]

Great, thanks - I had imagined having to fashion a sliver of wood all along the joist - just raising at fixings sounds much easier.