First you need to decide what type of noise transmission you are trying reduce. Are you just trying to increase the perceived quality of the space? Do you tend to stay up & watch telly after your better half has gone to bed? Or are you concerned that SWMBO will take up samba dancing & practice with ten friends in the bedroom while you're trying to listen to Radio 3 in the room below?

Airborne noise transmission can be reduced by adding weight to the floor/ceiling. Reverberation & ducting of noise to adjacent spaces through the joist void can be reduced by adding absorbent material to the joist void. Impact noise can only be reduced by isolating the floor from the ceiling.

Putting a resilient layer on top of the chipboard (e.g. woodfibre) & resilient bars in the ceiling below will significantly reduce impact noise. For improved performance add a floating floor on top of the resilient layer using a high density board (e.g. Cellecta ScreedBoard 20 or Knauf Brio) & two layers of high density plasterboard (e.g. 15mm Gyproc SoundBloc) to the ceiling below.

http://www.viking-house.co.uk/soundproofing.html

Where the finish is carpet, acoustic underlay will be much more cost effective than the resilient layer/floating floor approach, but you may still need the latter in tiled/linoeleum areas, so think about how the levels will work out.

Some composite products are available which combine resilient layers with other products, e.g. battens or floor boards, but these are generally not good value. They sell because they allow developers to achieve defined levels of performance without needing too much specific knowledge. In your situation they're probably not worth the money.

David

Plasterboard planks are for adding mass to the structure. Resilient layers are made from materials which can be compressed in the short term, but quickly return to their original thickness. They are usually woodfibre, foamed polyethylene, recycled rubber or recycled/synthetic felt.

The other option is to use top hat type resilient profiles on top of the joists, but these need to be fitted before the structural floor, are not great from a safety point of view & from my limited experience at work, not particularly effective. The detail I guess you're thinking of is this one:

http://www.british-gypsum.com/white-book-system-selector/systems-overview/gypfloor-silent

David

Posted By: davidfreeboroughFirst you need to decide what type of noise transmission you are trying reduce. Are you just trying to increase the perceived quality of the space? Do you tend to stay up & watch telly after your better half has gone to bed? Or are you concerned that SWMBO will take up samba dancing & practice with ten friends in the bedroom while you're trying to listen to Radio 3 in the room below?

Thanks for the very constructive answer David. There's definitely a general intention to improve the perceived quality. There are a couple of places where I'm specifically concerned. I do listen to loud music in the living room sometimes and don't want to annoy others. There's also a ground floor guest bedroom which is below the bathroom and the MVHR unit and is next to the living room and I'd like the guests to have a chance of sleeping! So consider it as self-interest if you ever come to visit.

Posted By: tonyI always nail the ceilings up first, sound insulation batts or quilt, then lay the floor, makes it all so easy. then do as above or similar, it is difficult to nail to steel so may be screws.

I guess you haven't done many metal web joist floors? Or built houses like straw bale where the structural first floor is needed to build the first floor walls? But whatever the merits, the situation I'm asking about is where the floor is constructed before the ceiling, and I'm asking precisely because it may need different solutions.

Posted By: Nick Parsonscould you put a reminder at the start of a new thread that whatever you are discussing is in the context off a straw build

I'll try to remember Nick but I don't think it's all that relevant here because we're discussing the internal structures, which are pretty conventional. I don't think it's usually the external brick walls that are the problem, more often internal floors and partitions.

I don't know about metal web joists but the best practice for sound proofing floors is to have separate joists for the floor and ceiling below so they are totally decoupled. Sound insulation "woven" between them.