Stud wall insulatiom

[theflyingpig]

What would people reccomend as a good insulation product to fit into an internal stud wall? The wall is between a future guest bedroom and the lounge, so acoustic properties probably most important...

Thanks!

 

[theflyingpig]

I built the wall out of 4x2, so can fit 100mm thick insulation... My studs are at 400mm centres...
I dont understand why the rockwool slabs are 450 mm wide!

 

[^woody^]

I dont understand why the rockwool slabs are 450 mm wide!

Because those ones are for cavity walls

 

[phatboy]

I built the wall out of 4x2, so can fit 100mm thick insulation... My studs are at 400mm centres...
I dont understand why the rockwool slabs are 450 mm wide!

Rockwool sound insulation is 600 wide, which is also annoying. I turn it on its side, so end up with 3x 400mm sections out of a 600x1200 piece

 

[theflyingpig]

Seems odd they don't make one that's 400mm wide!

 

[^woody^]

Seems odd they don't make one that's 400mm wide!

They do. On a 1200 wide roll it's pre cut into 400 and 600 and you break it at the width you need.

 

[theflyingpig]

Rockwool Flexi Acoustic Slab 33kg/m3 (1200mm x 600mm x 100mm) Pack of 6 (4.32m2)

Rockwool Flexi Acoustic Slab design allows it to be fitted snugly between frames, both timber and metal, without leaving gaps and without having to be cut to size.

www.buildingmaterials.co.uk

 

[^woody^]

Designed for cavity walls

 

[phatboy]

They do. On a 1200 wide roll it's pre cut into 400 and 600 and you break it at the width you need.

Would you recommend that type? Ive read that its 10kg/m3, which meets regulations. Where as the Rockwool range of solid slabs vary from 30 - 100kg/m3

 

[^woody^]

Would you recommend that type? Ive read that its 10kg/m3, which meets regulations. Where as the Rockwool range of solid slabs vary from 30 - 100kg/m3

Always go for the best db rating. I don't know if denser Rockwool automatically relates to better sound reduction for any given thickness, may do, but there seem to be other quilts that are not as dense as Rockwool but meet b/ regs requirements.

Incidentally, if sound is a big issue, pay attention to the actual frame design not just the insulation.

 

[oldbutnotdead]

What @^woody^ said especially frame design. Are the floors/ceilings solid concrete or more normal joists/plasterboard? If they are normal then you've got 2 excellent noise pathways there- through the floor and ceiling voids and conduction through the structures.
Mass is always good, ideally you'd decouple the surface from the framework (look for resilient bars/fixings, green plasterboard glue)
The acoustic separation of a 100mm wall may satisfy building regs but that doesn't mean you'll be happy with it.

 

[jeds]

There are several ways to satisfy regs for internal partitions, some requiring mineral wool, others not. The main requirement if you do use mineral is that is must be minimum 25mm and minimum density of 10kg/m³. Most people use loft roll, although some cheap brands don't quite reach that so, technically, don't comply. But I've never, ever, known it be a problem.