Basic terminology!

[dodgydiy]

Hi
I am building an internal wall ( non load bearing). I am confident in my abilities, but a little unsure of the terminology used.
The wall will enclose a stair case and must reach fire regs as we are having the loft converted.
1) What is meant by "400mm centers", is it the distance between the uprights??
2) There is no mention in the plans of any horizontal supports, would this be because they are not required, or would they be standard which the architect has assumed I know??
3) At what intervals would you fix the frame work to the floor, ceiling and existing wall, and any particular size of nail/screw??

I realise this is fairly basic stuff, but I'm a better DIYer than I am a scholar!!
Thanks in advance.

 

[salem2000]

The 400mm centers, is the distance between the centers of the uprights.

This might help:

Here

 

[AdamW]

You generally choose your "centres" to correspond with the size of board used. So, if you are using 2400mm x 1200mm plasterboards, having the studs at 400mm centres will exactly divide into 1200mm.

If you were using e.g. 1200x900 boards then you would have your studs at 300mm centres ideally, but more likely 450mm centres.

It means that you end up having to do far less cutting, which also means that if you are using tapered edge boards then you don't need a skim.

In terms of your horizontal supports, aka "noggins", I personally would put them in but I am a diyer. Plasterboard needs adequate support or it will bow slightly. I feel that noggins around half way up and staggered (so one noggin is at 1200mm above the floor, the next at 1300mm, then 1200mm, then 1300mm and so on) would help support the plasterboard.

You should ring your architect and ask about the noggins though. Although I doubt it would hurt to have them even if they aren't needed.