Insulated Plasterboard on top of Soundbloc

[ashthekid]

Hi,

 

I'm looking at the layers of my planned pitched roof in a very large room:

1) Rafters with 100mm insulated between

2) 50mm rigid insulation

3) 25mm battens

4) 15mm soundbloc

 

For extra thermal protection and to get the U Value down I'm considering adding a layer of insulated plasterboard(like Celotex PL4000) before the soundbloc? Can this be done? Has anyone else experienced a design like this?

 

[tonyshouse]

Don’t like the sound of the battens, they may facilitate thermal bypass 

 

the more insulation the better especially with high ceilings 

[ashthekid]

The battens are primarily to allow the soundbloc layer to really do it's job.

But I am worried I haven't enough thermal protection on such a high large open space. It's approx 10m x 8m with very high vaulted ceiling's..

[nod]

Forget the batons Insulated PB

Resilient bar Then sound block 15 mil  

[Conor]

Up the 50mm rigid insualtion to 100mm (assuming it's going under the rafters)

[ashthekid]

Yes it’s going under the rafters.

 

The contractor gave me the impression that resilient bars don’t really make that much difference compared to battens.