 Finishing??
I have heard of a new technique used by another developer that exactly matches your description. The plasterboards are applied directly to the walls or studwork. This is the same as the traditional drylining however this new method doesn't require a skim coat. Decoration can be applied directly to the pasterboard.
We have a new GW house with the traditional plasterboard/skim coat and we had much sagging and bellying. Over many 6' runs with a straight edge, the gap beneath it varied from 0 - 3/4" in places. After the usual 'ducking & diving' from GW aftercare we eventually had the plasters back in to do the job properly. It really annoys me how they always flatly deny problems until you show persistance. When they can see that you either a) know what you are talking about or b) aren't going to fall for their feeble excuses they then eventually do the work that they should have done when you first raised the issue!
I believe the NHBC do have some guidelines on what is acceptable. As also pointed out above I would also suggest having a plaster view the work and give you direction as to how significant the 'bellying' is.  |