Author Topic: Soundproofing an already converted garage conversion (cinema room)  (Read 2159 times)


  • Guest
Hi all.

Not quite for a band but more for me listening to my home cinema setup...

I am looking for some advice and hoping people can help. I have read around on soundproofing but am slowly going nuts I think trying to take it all in, and I'm very worried about getting it wrong!

I am currently in the process of converting an already converted garage conversion into a cinema room. I have a fairly good idea on decor and kit, but I am struggling with the soundproofing element.

The room is 4mx2.4m long/wide with a large window filling most of one wall and an interior door about half way down one wall. We also have a pillar half way down one wall running floor to ceiling into which the fuse box is mounted - the column protrudes about 8cm. The floor is/will be tiled (although I may be carpeting now I have heard tiles are bad in this type of scenario).

I am really at a loss for how to soundproof the room. Current thinking is to overboard the existing walls with 12.5mm acoustic board with a layer of green glue, then place another layer of the same with another layer of green glue. Would this provide effective wall soundproofing if screwed into existing plasterboard? I'm worried that the weight will pull the wall down! I should mention that at just 2.4m wide, space is at a premium in here.

The ceiling I am less worried about because I can overboard that and put rockwool in the cavity but again, any advice on this would also be appreciated. I really cant afford to lose too much width off the room but if its a must have to ensure it all sounds OK (and doesn’t disturb the wife!) then I would obviously.

I guess I'm hoping someone will come along and say "I did that, its great"!

Thanks for any help!
(as a side note, for the verification question, I had no idea what color the sky is when viewed from space!)


  • Guest
Re: Soundproofing an already converted garage conversion (cinema room)
« Reply #1 on: July 11, 2013, 06:36:52 AM »

Two things I must ask you.. how MUCH isolation do you require? Let's get it to a number in decibels. Do you have a sound level meter? Can you get us some readings?
That was one question... haha! ~facepalm~

Next is How high is the ceiling??

A drawing of your room/converted garage would help. It's difficult to know exactly what you need without more information. Post some photos and drawings with measures in 3 dimensions (H-W-D-)

I have a paper on my publications page, "How to find out how much Isolation you need.pdf" that should be of help. Could you tell us how loud your system usually is on average; -- dBA?



  • Guest
Re: Soundproofing an already converted garage conversion (cinema room)
« Reply #2 on: September 02, 2014, 12:39:38 PM »
A good post here. Help the many people who have knowledge of your posts.