Sound proofing

[synaesthesia]

A little off-piste for this one, but work related!

We have an office sat between 2 classrooms, with walls that are primarily stud walls which replaced old folding doors many moons ago. The noise transfer is ridiculous and is often impossible to work in our own office if there's rowdy classrooms or excitable teachers. Just as worrying is the concern of people hearing our conversations or certain words uttered when toes are stubbed a UPS!

We have *extremely* limited budget so I feel bad asking for this, but our SBM and head have insisted I'm right to investigate options and they'll do what's needed.

There's not a huge amount on each wall electrically so there's no issue with adding something on top - whether it's specific sound proofing boarding, an additional insulated stud wall or something. Ideally want to avoid taking out what's already there due to the mess involved, but if we have to, we have to.

 

The options we have already considered are:

Removing our internal plasterboarding, adding insulation, replacing plasterboard with new acoustic plasterboard, tape, plaster, paint, make good & refit services. Doable for £400ish, a LOT of mess, week's work. No loss of space.

Building a secondary stud wall onto existing, leaving old plaster in place. Insulate, fit new acoustic plasterboard, tape, plaster, paint, make good & refit services. Add another £100 for extra timber, much less mess and work. Loses circa 500mm of office space.

 

I can see lots of "acoustic panelling" available, basically felt backed MDF panels but all these appear mostly cosmetic, and it really pi**es me off they're marketed as "acoustic". That sort of idea though would be perfect, as we'd just have to adhere them to the walls we have and could do it in a day.

Has anyone got any experience of doing something like this? Maybe any recommendations of materials or solutions that would help?

I don't know a huge amount about sound travel, and googling around shows a fair bit of information which I can't verify but does sort of make sense, for instance if the stud walls already in place don't have any insulation, are sound waves "bouncing" around in that cavity and making it worse? In which case, would we need to strip it out anyway?

I think anything over a grand is likely to be a non-starter. Not a huge office, the stud wall sizes are 4.5m x 2.5m each wall.

[Andrew_C]

You need to add mass, ideally isolated from the existing wall, with NO gaps.

 

So, add a new stud wall with thick plasterboard, but everything "floating" on neoprene pads.

 

Oh, and not expecting too much...

[Andycat]

The acoustic tiles/boards aren't for sound PROOFING, they're great at sound TREATMENT (ie noise in the same room).

 

PROOFING is as you say, insulation, thicker walls etc.

[DalekSec]

After dealing with issues with our internal call centres, our sound dampening (not proofing as suppliers kept telling me!) was panels on the wall and ceilings, worked a treat for voices, you will need them in your office and the rooms next door for full dampening 

And carpet not solid floors

[synaesthesia]

The joys of language!

No chance we can do anything in the neighbouring rooms due to the services on the walls unfortunately.

 

A couple more ideas have come up:

https://www.noisestopsystems.co.uk/shop/wall-soundproofing/noisestop-2-panel/ - just under £600, minimal intrusiveness and an apparent "46db" reduction in sound although pinch of salt I assume that will be for particular frequencies etc. (a few variants of the same product available)

 

And another I'm just looking into more, https://soundstop.co.uk/products/tecsound-100-acoustic-membrane?variant=43491337011423 - thinking a layer of that with some 12mm MDF over the top (because site would rather not deal with plasterboard if we can help it )

So in both cases that's just adding mass, I don't think there's any chance of isolating as we'd lose too much space.

 

[machy]

Several really thick curtains might be a cheap solution if you just need a bit of it

Can't remember if that's just to help in room though 

[synaesthesia]

Yeah think that's likely to be more in-room.

Edging towards a combination approach at the moment as one wall has an ancient radiator on and huge pipes, so thinking about fitting a stud wall to that and boxing those in, and going for a tecsound/acoustic plasterboard sandwich on the other wall

[Andrew_C]

Plasterboard isn't difficult, is cheap, and is massive.  Stick some OSB up first, then anything you want to hang on the wall gets screws through the plasterboard into the OSB.  Easy.

[Chris_Cook]

We had something done at home with a stud wall.

 

A builder cut a horizontal slot in the plaster board on one side - about 1 foot high by the width of the wall. This was enough to feed fibreglass insulation into the wall. Not perfect, but cut down a lot of noise. The plaster board can then be put back after and plastered / painted.

 

That might be less disruptive than removing the whole side of the wall.

 

Another thing to check is that the stud wall goes all the way up beyond the false ceiling. If there is a gap above that might let sound through.

 

Also make sure the draft strip is in place on all the doors.

[robintech]

2 hours ago, synaesthesia said:

So in both cases that's just adding mass, I don't think there's any chance of isolating as we'd lose too much space.

 

 

That could be the best option if there's no  real mass on the existing stud wall and easier than building a new wall https://www.youtube.com/watch?v=ZHwa3dYBQsI . Would still try and seal the existing one or stuffing insulation in it somehow as Chris_Cook said

 

 

[southhamster]

Stick on cork tiles? Might be worth a try.

[synaesthesia]

16 minutes ago, southhamster said:

Stick on cork tiles? Might be worth a try.

Doesn't add any mass - might dampen the noise in our office but wouldn't do anything to stop us tearing our hair out and learning more about GCSE/A Level Business than most of the students in the actual classroom.

 

@robintechI'd seen another one of their videos and watching that one is interesting - it'd cost just over a grand to do the office in those Soundboards but using the same idea, I'm considering using MLV sheets with 12MM MDF over the top and should provide more than a 10dB drop to effectively half the volume. (The figures are 16dB for the sheet alone, so probably a little more with the MDF, so 10 is worst case scenario but still acceptable).

 

One wall however has pipework which is sort of boxed out and I might use that to advantage a little - i.e. just the MLV and MDF on one wall, and add a secondary insulated stud wall, with MLV and MDF on that one. Even with the extra timber, we shouldn't break £600.

 

[jmak]

I presume when you're talking about £400 plus a week's work, you mean a week of an employee's time - which is fine as long as they're not taken away from doing something they're paid to do and their time is less expensive than a contractor.

[synaesthesia]

2 hours ago, jmak said:

I presume when you're talking about £400 plus a week's work, you mean a week of an employee's time - which is fine as long as they're not taken away from doing something they're paid to do and their time is less expensive than a contractor.

Of course, this has naturally already been discussed with those people and I would also be helping  Contractors are out of the question, but won't be necessary anyway for something this menial - the only awkward bit is turning off the mains as a failsafe when we take a short lump of trunking off the wall. 

I think we're now looking at 2-3 days max although a little more initial outlay, and I'll likely be doing the making-good myself.

[SamanthaD]

I watch a lot of Soundproofing Expert on YouTube - they design and build soundproof drum rooms etc.

 

Main thing they always say that's relevant to this is anything that is sold as acoustic or soundproofing is likely no better than the standard equivalent. They don't use acoustic plasterboard, just 2 layers of standard plasterboard, with a staggered fit. Also different densities of materials is important to absorb different frequency ranges, so they use different densities of Rockwool with the plasterboard, OSB outer skin etc and make sure it's sealed with silicone.

 

A different alternative may be acoustic masking - not my forte at all but I've heard (get it?) great things. Might be worth a look.

[synaesthesia]

They're the folk I've been speaking to  The specs of the "acoustic" plasterboard definitely suggest improvement due to much higher mass, and along with the extra steps you mention should allow for at least some improvement. It's not a huge amount of money, just a lot of work but we might be able to bear in mind for similarly afflicted rooms in future.

I've also looked at masking, assuming you mean the devices which effectively "echo" to sort of cancel out the noise, but I'm not sure how effective that could be against an ever changing cacophany of noise.,

[SamanthaD]

3 minutes ago, synaesthesia said:

assuming you mean the devices which effectively "echo" to sort of cancel out the noise

Not quite. Have a look at https://www.softdb.com/sound-masking/ - explains it better than I ever could. I heard one of their specialists - Hanieh Motamedian - talk at a conference and she knows her stuff on this!

[synaesthesia]

Ah, I see. Intriguing, probably not a silver bullet but certainly neither is sticking loads of crud on the walls. 

Hopefully SLT give the thumbs up soon and we'll see what we're allowed, hopefully for a summer install and a more peaceful September!

 

Doesn't help that our year 11's are, due to the time of year, bouncing off the walls like red-bull soaked power balls!