Sound proofing external facing stud wall behind a garage door

[Alex B]

Hey guys, I'm building a stud wall behind my garage door (metal door) to use as a recording space and I'm wondering about the best materials to use to create a good sound barrier with good thermal performance too. I was thinking about using 4x2 to make the frame and on the side facing the garage door cover it with some high density material. I'm not sure if that could be OSB as it seems to be more resistant to humidity as well. Inside the wall I'm planning to add 90mm PIR insulation, and then on the inside 1 layer 15mm acoustic plasterboard with a layer of tecsound and then another 15mm layer pf acoustic plasterboard.

I'f anyone has any other suggestions about different materials I could use it would be great.

[John Walliker]

Consider filling the voids in the stud wall with dry sand. This adds a lot of mass but also has a lot of internal friction which helps convert the unwanted sound into heat. It is usually best to try and absorb as much of the sound as possible rather than just reflecting it away. One you have the stud wall in place, then make a completely separate secondary wall with a space of a few cm between the two walls. Stick some fibreglass wool in that intermediate space. Such a double wall with sand in each wall doesn't need expensive materials but will probably have far better sound insulation than the rest of the garage - especially the roof.

John

[Martin Brown]

How noisy is it outside? There is no point in having a single wall that is acoustically perfect when the 5 other surfaces are still rubbish.

The 2" dense rockwool fibre board is a pretty good acoustic insulation but thick flock/velvet folded curtains can be a lot more cost effective.

It all depends what kind of room acoustic you are trying to create and how much time and money you are prepared to spend on doing it.