Best wall for sound insulation

[le-cerveau]

My design is moving on and I now have an ICF supplier (wall and slab) (Econekt) and a Structural Engineer is working out all the details, which means I have 3-4 support posts (Steel) within the original internal wall structure, 2 x steel beams and 250mm thick Widespan planks to make up the first floor (8.6m spans).  What this means is that all my internal walls can now be anything, ICF / Block / Stud, with no requirements for thermal insulation the question is what will provide me the best sound insulation?

[ragg987]

Depends on your objectives for sound insulation - the best would be something that is "studio" grade and can attenuate across the frequency range that you wish to manage. If your noise includes low frequency (e.g. deep bass <40Hz) then your task becomes harder - the UK domestic standards are biased towards mid-range (e.g. speech or TVs).

 

So, the "best" for wide frequency range will be a room-within-a-room. This is generally a floating floor with a fully-sealed structure standing within that. You need to take care of the 3 methods of sound transmission: through air (by sealing all gaps, special care for doors and windows), through vibration (by adding resilience / damping) and through transmission (by adding mass). This is not a trivial undertaking to do properly, you cannot just treat one wall and expect it to be effective.

 

Of course, if your objective is just to select between ICF / block / stud based on best-effort sound reduction then the above does not apply. I would be inclined towards ICF in this case as it provides mass and is fully sealed all round.

 

Here is a good site for some background and specific link to room-within-a-room: http://www.soundproofingcompany.com/soundproofing101/building-a-room-within-a-room/

 

I have just built a basement room for listening to music and home theatre, happy to share any details it that helps.

[le-cerveau]

I am not looking for room in room, just the best general sound insulation between all house rooms.

 

The one issue with ICF internal walls is they will be 250mm thick plus plastering, whereas stud/block will be closer to 100mm.  Stud work would be easier, particularly for electrical fit but then I would have to use the correct filling and boarding, so not sure of advantage over a traditional block wall?

[jfb]

block is going to be better than stud work for sound insulation -  the denser the blocks the better for sound. 

[tonyshouse]

Poured concrete better still

[ragg987]

42 minutes ago, jfb said:

block is going to be better than stud work for sound insulation -  the denser the blocks the better for sound. 

Not sure this would always hold. Block might address the mass aspect (block can also be filled with air and be very light), but sound will also transfer by other means. Stud has the advantage of being 2 separated leaves and this is an important factor in sound attenuation, especially if you create a larger gap and can add fibre insulation in between.

[curlewhouse]

Actually, this is what I was thinking of using some spare loft insulation rolls I have for. I've been toying with "hanging" them inside the stud walls of the main bedroom and lying them under the floor too (Its an upstairs room). My wife is a nurse and works nights mostly, so a quiet room through the day is a great thing - though it's very quiet where the house is going anyway, so most noise would be from inside the house itself. Not sure if sound transmission through the studs from one plasterboard to another would cancel out any advantage or if it would be the otherwise empty voids which would be the main culprits and thus make this worth doing.

[tonyshouse]

Dense rockwool batts would work better and if a job is worth doing etc....

 

min in one side 12.5 + 15mm p board and the other just 12.5 this is minimum.

 

no air paths , no back to back sockets or light cwitches plenty of quilt in floor and above ceiling

[puntloos]

I'll revive this 2016 topic (ha). But I have a similarish question, primarily shielding downstairs livingroom from upstairs, but in-between rooms upstairs still important (they just won't have a serious home cinema  )

 

- House is going to be standard masonry build

- Internal walls completely open for discussion, within reason, but perhaps max 350mm, ideally more like 250 total width?

• Assuming solid block?
• How to build it up? I think perhaps the double stud might be better instead? (why not double block?). That site is unable to tell me actual wall widths for some reason. Sigh.
• How do you include sockets? what about the horizontal service void? 

- Ceiling - let's assume a standard block and beam ceiling - 220mm and 200 void. 

• Same story really, how much 'thickness' should I allocate beyond the standard brick/beam?
• I'll probably safely fill most of the void with "some material" but of course there will be things in the void. Light fittings, a projector screen in one spot.. etc

[Mr Punter]

With a 100mm block wall you could fix 25 x 50 vertical battens infilled with Rockwool, 16mm horizontal resilient bars and 15mm soundbloc plasterboard.  Do this both sides and it only adds 112mm to the bare block size.

[puntloos]

To be clear I assume you are talking about the normal walls, not ceiling:

1 hour ago, Mr Punter said:

With a 100mm block wall you could fix 25 x 50 vertical battens infilled with Rockwool, 16mm horizontal resilient bars and 15mm soundbloc plasterboard.  Do this both sides and it only adds 112mm to the bare block size.

 

Not bad. That should be pretty decent. But the 'room inside a room' design effectively is 2 walls, could I perhaps do 2x75mm block with a 75mm airgap between them, or would that be worse?

[puntloos]

One interesting thing that I noticed is that very very VERY few companies speak about a double block wall. All 'pro' sound insulating walls seem to be timber/stud, but most companies do say "more weight is better" so surely block is better as a principle?

 

 

[puntloos]

Re-highlighting this for a moment..

 

I'm still thinking something in the direction of:

 

soundbloc plasterboard (15mm)

block(75mm)

vertical battens w/ rockwool (25mm)

block(75mm)

soundbloc (15mm)

 

Sounds... fairly soundproof at 205mm no? Or did I miss something

But:

 

- How would you insert the horizontal service void, just cut it out of the soundbloc? Or trying to scrape it into the block? DOesn't have to be massively deep I imagine..

 

[Iceverge]

How much noise do you expect to have to deal with? 

 

That cavity wall may not perform as well as you think (although it will be very good)  and will require chasing etc to get your wires in.

 

I would lean towards a metal wall system. 

Have a play with the below. 

 

https://www.british-gypsum.com/white-book-system-selector/partitions

 

 

[SimonD]

23 hours ago, puntloos said:

Re-highlighting this for a moment..

 

I'm still thinking something in the direction of:

 

soundbloc plasterboard (15mm)

block(75mm)

vertical battens w/ rockwool (25mm)

block(75mm)

soundbloc (15mm)

 

Sounds... fairly soundproof at 205mm no? Or did I miss something

But:

 

- How would you insert the horizontal service void, just cut it out of the soundbloc? Or trying to scrape it into the block? DOesn't have to be massively deep I imagine..

 

 

As always, the devil is in the detail. Generally speaking dense walls do insulate sound better. However, the materials used in the wall also affect the acoustics in the room.

 

So when designing your acoustic walls, you need to consider both the sound levels and what you're looking to achieve. Is it sound insulation between rooms only or do you also want to reduce room reverberation, which means using sound absorption materials.

 

For sound insulation, the minimum cavity recommended in a block wall for reaching Building Regulations requirement in new builds of 45db would be 75mm. So with some dense blocks, you can achieve this just with wet plaster, some 75mm blocks, or 100mm blocks, 75mm cavity and then wet plaster.

 

With respect to service void, I'd avoid any chasing in the masonry as this will reduce sound insulation. Probably better to build an additional service void which could use acoustic plasterboard to improve the overall performance of the wall.

 

Here's a pretty useful document by British Gypsum giving various wall buildup examples and sound insulation levels.

 

HTH.

LIT_Stockist_Guide_Construction_details_02.pdf

[puntloos]

18 hours ago, Iceverge said:

How much noise do you expect to have to deal with? 

 

Let's just say I have two 1000W subwoofers and a 3 year old toddler. (who will be 12 in no time..)

 

18 hours ago, Iceverge said:

That cavity wall may not perform as well as you think (although it will be very good)  and will require chasing etc to get your wires in.

 

I was debating the "horizontal service void" idea people mentioned elsewhere but I think it'll impact the wall too negatively. 

But of course(?) I'll be inserting a lot of ducting etc pre-emptively. Should be okay?

 

18 hours ago, Iceverge said:

I would lean towards a metal wall system. 

Have a play with the below. 

 

https://www.british-gypsum.com/white-book-system-selector/partitions

 

Interesting, no load bearing walls though. 

 

How would you build up a good load bearing one?

6 hours ago, SimonD said:

 

As always, the devil is in the detail. Generally speaking dense walls do insulate sound better. However, the materials used in the wall also affect the acoustics in the room.

 

So when designing your acoustic walls, you need to consider both the sound levels and what you're looking to achieve. Is it sound insulation between rooms only or do you also want to reduce room reverberation, which means using sound absorption materials.

 

Well, the thing is - I want "good sound isolation", however the room itself should stay "normal". I don't want to create some cinema (dead room) that sounds very unnatural for normal living. I'd like a "as neutral as possible" wall (so not really reflecting a ton) that does 

 

6 hours ago, SimonD said:

 

For sound insulation, the minimum cavity recommended in a block wall for reaching Building Regulations requirement in new builds of 45db would be 75mm. So with some dense blocks, you can achieve this just with wet plaster, some 75mm blocks, or 100mm blocks, 75mm cavity and then wet plaster.

 

What's the reg? Between walls? Or external?

 

6 hours ago, SimonD said:

With respect to service void, I'd avoid any chasing in the masonry as this will reduce sound insulation. Probably better to build an additional service void which could use acoustic plasterboard to improve the overall performance of the wall.

What's "chasing"? (sorry hard to google since it's a generic word)

 

6 hours ago, SimonD said:

Here's a pretty useful document by British Gypsum giving various wall buildup examples and sound insulation levels.

 

HTH.

LIT_Stockist_Guide_Construction_details_02.pdf 2.31 MB · 0 downloads

Ha, same doc.. but again not "load bearing"

[SimonD]

On 10/04/2021 at 19:37, puntloos said:

Well, the thing is - I want "good sound isolation", however the room itself should stay "normal". I don't want to create some cinema (dead room) that sounds very unnatural for normal living. I'd like a "as neutral as possible" wall (so not really reflecting a ton) that does

 

Designing a room and furnishings to reduce noise in the room is a bit of a mathematical task where you really need to know the typical noise profile you're dealing with in the room and what sounds you need to absorb. For example, for a porous material to be effective for a given frequency, it's thickness has to be a quarter of the length of the sound wave.

 

Easiest way to deal with your needs is to focus on reducing sound transmission through the wall and then use soft furnishings etc.within the room on a trail and error basis to get to results you need.

 

On 10/04/2021 at 19:37, puntloos said:

What's the reg? Between walls? Or external?

Building regulations Part E , between walls.

 

On 10/04/2021 at 19:37, puntloos said:

What's "chasing"? (sorry hard to google since it's a generic word)

 

Chasing a wall to embed pipes or cables.

 

On 10/04/2021 at 19:37, puntloos said:

Ha, same doc.. but again not "load bearing"

 

With the masonry wall, it doesn't matter. If you're using blocks that are capable of taking the load, it can be load bearing or not. Same sound insulation properties.

[puntloos]

On 17/04/2021 at 09:33, SimonD said:

 

Designing a room and furnishings to reduce noise in the room is a bit of a mathematical task where you really need to know the typical noise profile you're dealing with in the room and what sounds you need to absorb. For example, for a porous material to be effective for a given frequency, it's thickness has to be a quarter of the length of the sound wave.

 

Easiest way to deal with your needs is to focus on reducing sound transmission through the wall and then use soft furnishings etc.within the room on a trail and error basis to get to results you need.

 

Building regulations Part E , between walls.

 

 

Chasing a wall to embed pipes or cables.

 

 

With the masonry wall, it doesn't matter. If you're using blocks that are capable of taking the load, it can be load bearing or not. Same sound insulation properties.

 

 

Thanks Simon, I'm not 100% clear though on my internal walls. In particular I have a "central wall" on the ground floor that I assume will have to take "most of the house weight" 

Current buildup plan is as mentioned - about 215mm masonry-based:
 

soundbloc plasterboard (15mm)
block(75mm)
vertical battens w/ rockwool (25mm)
block(75mm)
soundbloc (15mm)

 

Am I understaning correclty that the "battens w/ rockwool" section needs to be 75 at least?

The design I listed should surely suffice to block meaningful sound?