Small outbuilding

[theDIYkid]

I chaps
I have an outbuilding built already with breeze blocks and stone outside and slated roof...I want to make it a bit longer so need to take the wall out a bit to make an entrance and reuse the stone and breeze blocks. I want to add Rockwool R45 for soundproofing better for a music room, does the Rockwool go between the breeze blocks (inner wall) and stone (outer wall) or should I put it on the inside on top of the breeze blocks then plasterboard that?

What size gap between the 2 layers? the Rockwool will be 50mm.
Thanks

 

[Tigercubrider]

I would build a 4x2 framework inside the building. Don't fix it to the walls, leave it freestanding. Sit it on neoprene about 1" thick in 4" strips. Put the rockwool in the gaps and screw plasterboard over the top. Fill any gaps- Then apply a second layer of plasterboard over the first, staggered so the seams don't match. Fill again and ideally plaster.

 

[theDIYkid]

I dont really know what you mean by neoprene? I was going to add batons to the inside and fit the slabs between them then plasterboard, meaning I dont out any insulation between the external brick and internal breeze block? thanks

 

[Tigercubrider]

The idea is to have an isolated inner room. The whole inner structure should sit on neoprene (rubber) so that sound isn't transferred to the slab.

The rockwool sits between the inner structure and the outer. It will provide thermal as well as acoustic insulation

https://shop.deltarubber.co.uk/rubb...rubber-strip/solid-neoprene-rubber-strip.html

 

[Tigercubrider]

And use acoustic rockwool not thermal

 

[theDIYkid]

Thanks man will get some of that rubber and this goes under the newly built wood frame. So use rockwool r3 or rwa45 slabs internally on the inside frame then plasterboard on top...and the cavity between the skins walls of 100mm add normal 50mm Insulation there too? That right