Internal brick wall vs plasterboard - cost and acoustic?

vichan · Nov 12, 2023 9:37 pm

Hi all,

Good day. We are considering a new build in Sydney, and would like to understand the cost and acoustic of internal brick wall vs plasterboard.

- Would plasterboard with acoustic batts acheive the same soundproof level of internal brick wall?
- Read on forums that doubling the plasterboard / using SoundChek / SuperChek with acoustic batts will be good for soundproofing? Would that be as good as internal brick wall?
- Cost wise, how different will it be for internal brick wall vs standard plasterboard? Let's say 50% or more or less?

Thanks a lot in advance

Kind regards

gommeqld · Nov 13, 2023 8:57 pm

You cannot simply compare plasterboard with brick. Each can meet your acoustic requirements but the important thing to remember is the thickness and material content of each wall. There are many combinations. I recommend you spend some money and meet with an acoustic engineer to discuss what you want to achieve.
But first ensure you study and understand the meaning of the acoustic ratings of materials and wall construction and be clear on what you want to achieve. I did and found that very few "professionals" in the building industry had any idea of how to build a soundproof (sound resistant) wall. That's why I recommend speaking with someone who actually knows about these things - that is, an acoustic engineer.

alexp79 · Nov 14, 2023 7:41 am

110 mm solid brick wall with render is not really performing very well acoustically (it provides STC of around 45-48 depending on the thickness of render). A bit better in comparison with standard plasterboard wall on 90 mm timber studs filled with 'acoustic batts' (which performs to STC 40), but really nothing impressive.

If you use metal studs with 2 layers of 16 mm plasterboard and green glue between layers (and batts of course) - you will easily outperform 110 mm solid brick by far (e.g. STC of 55), but if you add resilient channels, then you have a chance of obtaining STC 60+.

vichan · Nov 15, 2023 7:33 am

Thank you alexp79 and gommeqld for your advice, that's very helpful, thanks