Stud walling a door opening

[broody]

I'm filling in an internal doorway, stud frame with plasterboard. It's 204cm tall and 80cm wide. It's 13.5cm - 14cm deep, it varies, I've read I need about 3mm resess for the plasterer to skim.
B&Q does
C16 Stick timber (T)45mm (W)70mm (L)2400mm, this plus two layers 12.5mm board gives me 12cm total stud wall thickness, would this be ok?

Also, does the plasterboard have to be one sheet? I can't get a 2.4m sheet in my car, but I could get
Gyproc Standard Square edge Plasterboard (L)1800mm (W)900mm (T)12.5mm.

I'd have to have a join near either top or bottom of the door?

Thanks for any tips.

 

[23vc]

Is 70mm the actual finished thickness of the cls, or the nominal size?
You mean total of 4 layers of pboard, right?
Yes join is fine, but put a stud there so the ends are fully supported.

 

[broody]

Is 70mm the actual finished thickness of the cls, or the nominal size?
You mean total of 4 layers of pboard, right?
Yes join is fine, but put a stud there so the ends are fully supported.

I'm not sure of the thickness, I assume the finished size?

 

[23vc]

the 3x2 CLS I've used is 60-something mm actual size, so I'd go and see it, measure it, see what else they've got which might fit better and go from there.

 

[broody]

the 3x2 CLS I've used is 60-something mm actual size, so I'd go and see it, measure it, see what else they've got which might fit better and go from there.

Great idea, thanks