Plasterboard - supporting at perimeter?

[low_and_there]

A question about adequate support for plasterboard... this is very noddy. I've read the NHBC guidance but looking for practical experience of what is really necessary:

 

I'm about to line a new ceiling in dormer. Joists are at 400 centres and had planned to use 12.5mm Plasterboard. The span is around 3.8 x 2.7m. There's one set of noggins between the joists in the middle of the longer span, per SE's spec, but there are no noggins at either end of joists. 

 

However, having read the NHBC guidance it seems that for anything less than a 19mm board, there should be perimeter support for plasterboard. I take this to mean that all edges should be supported (like when laying SE Ply or OSB on a floor), not just the actual perimeter of the room. Have I understood this correctly?

 

In the videos I've watched of people installing pb on a ceiling, it doesn't seem to be supported on all edges - only the room perimeter. In some videos from Australia, some folks appear to use 'back boards' to support joints.

 

On site do people really install noggins at all perimeter points for plasterboard or is it often the case that they are supported along the joists and at the edge of the room (i.e. not around all edges of the boards)?

 

NHBC reference: https://nhbc-standards.co.uk/9-finishes/9-2-wall-and-ceiling-finishes/9-2-4-dry-lining/

 

Thanks!

 

*I'm not planning to skim the boards - just joint compound, prime and paint. In case that makes any difference.

 

[jayc89]

I stud at 400 centres and nog every 600mm, belts and braces, but it gave a sturdy finish. 

[garrymartin]

Are the walls already done? i.e. will the ceiling plasterboard be supported by the wall plasterboard at the perimeter (wall butted up to ceiling) or are the walls already in (and hence ceiling boards butted up to wall boards)?

[Super_Paulie]

my builder added in supports all along the perimeter attached/overlapping the wall plate. Looks like he used any old crap he found in the garden to be fair, but couldnt hurt i suppose.

[joe90]

I too supported all edges (cuz I am OCD). I don’t always use noggins but a scrap of ply to hold edges between joists just holds the edges mid span.

Edited May 8 by joe90

[stu w]

Personally I think it makes a better and easier job with noggins around the perimeter 

[Gone West]

Our plaster boarder wanted all edges supported.

[MikeSharp01]

Makes sense to support all the edges, we have kept a pile of off cut battens to do it between boards on our boarding. 

[tuftythesquirrel]

Apart from making sense, if you don't, you wont have adequate fire resistance, if you haven't followed the M.I.'s. If the BCO comes round as you are doing it he could reject it as not fit for purpose.
Our space joist installation data says....

Plasterboard
Notes:.....  4. Perimeter and intermediate noggins are required to support the boards at their edges. Perimeter noggins are required for all board thicknesses and joist centres, whereas intermediate noggins are only required for the thinner boards at larger centres. See fire resistance tables