Acoustic insulation

Ok, just about to install the bars. Would I be right in saying these can't be double sheeted as they seem very flimsy.
 
stuart23 said:
Ok, just about to install the bars. Would I be right in saying these can't be double sheeted as they seem very flimsy.
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Lol we thought that when first encountered but they are designed for soundnloc double boarding so no problem plenty of screws and the right size screws is important if they go into the joist you might aswell have not bothered
 
Builderboi said:
Lol we thought that when first encountered but they are designed for soundnloc double boarding so no problem plenty of screws and the right size screws is important if they go into the joist you might aswell have not bothered
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Cheers for that, using 100mm knauf acoustic roll but can't help thinking I'd probably get the same sound resistance with 200mm of normal stuff. If the acoustic roll was 200 I'd understand but can't get my head round it. @Runswithscissors whats the difference?
 
Builderboi said:
Lol we thought that when first encountered but they are designed for soundnloc double boarding so no problem plenty of screws and the right size screws is important if they go into the joist you might aswell have not bothered
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What size screws you recommend?
 
It's the standard sizes of the top of my head is first board is 25 then 35. Or something u increase the size as each board goes on ccf usually supply us
 
stuart23 said:
Cheers for that, using 100mm knauf acoustic roll but can't help thinking I'd probably get the same sound resistance with 200mm of normal stuff. If the acoustic roll was 200 I'd understand but can't get my head round it. @Runswithscissors whats the difference?
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Hi Stuart

Acoustics is a serious black art... different sounds have different frequencies and therefore need different sorts of products to dampen them down.

This is not a particular area of expertise for me - you might want to contact Knauf Insulation Technical on 01744 766666 or Knauf Drywall Technical on 01794 416259.

I think that the main things tend to be increasing mass in the insulation and boards to dampen down the noise vibrations, then having air gaps to stop the higher pitched sounds... (be in some training discussions, but not really taking it in). Bigger issues are where you have hollow ceilings and floors between rooms.... I think you need to have a resistant bar fitted between the ceiling rafters (in opposite direction to the rafters) and the board below, to dampen walking noise above.... This means the boards below are not directly fixed to the structure directly taking the floorboards - seems common (and fairly cheap) in residential projects anyway

I know that on big hospital, hotel and residential schemes (like student accom), the client will employ an 'egg head' who specializes in acoustics... they will review and advise a spec for all areas.

All three of the drywall system manufacturers will have special wall and ceiling systems to provide specific acoustic performances

Sorry I can't help that much Marra

Rich
 
stuart23 said:
Cheers for that, using 100mm knauf acoustic roll but can't help thinking I'd probably get the same sound resistance with 200mm of normal stuff. If the acoustic roll was 200 I'd understand but can't get my head round it. @Runswithscissors whats the difference?
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Have a look at this page of Knauf Drywall Technical FAQ's

https://www.knauf.co.uk/technical-assistance/technical-faqs#q13

One is called - What is a resilient bar and how do I use it?

Might help....

Good luck!
 
stuart23 said:
Thanks for that rich. I've installed the bars already. I went with 100mm knauf acoustic, the bars then double sheeted soundbloc. I was just curious as to why the insulation was only 100mm when I could have fitted 200mm of normal stuff in.
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Think that mix of board, insulation and space is the best way...... Has someone advised you what to do?
 
Done few sound proofing jobs inc cinema rooms .
Most sound is vibration therefore transmitted through every static structure i.e. You can soundproof the ceiling but noise will be transmitted through the walls .
And once past a certain amount of proofing you are only gaining slight noise reduction per layer.
Having said that of course as the famous saying every little helps :sisi:
Resilient bars are good there is also a rubber matting not dissimilar looking to old bitu felt to go between sound boards also diff density foam mats which you apply direct with contact adhesive .(wear appropriate mask or just enjoy being off yer trolley like an old skinhead evo sniffer)
As said any static surfaces will transmit noise one to the other bars have to be fitted in certain way you can find info online.
Good luck may the monkey spanking commence.:reloco:
 
Any update on on the snooze block.. Interested to see pictures and know if she could hear you anymore Stu mate ?
 
Acoustic insulation
theplasterman said:
Any update on on the snooze block.. Interested to see pictures and know if she could hear you anymore Stu mate ?
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stuart23 said:
If the insulation touches the bars does that render them useless?
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Main issue as you will know I'm sure is not to accidentally fix the flexible part of the bar to any batten or metal /wood stud hence yes creating a static point .
Any boards or insulation again as long as not touching any edges of walls (unless also insulated for sound)so again edges to walls or pillars to be sealed with mastic to create flexible seal not transferring vibration ( noise).
I'm sure spec on ceilings is bars all running in one direction bar the last inverted. Maybe check on that as was 2 yrs ago since last one I did.
All info is found online.
 
stuart23 said:
There are 8 downlighters going in the ceiling so I presume that will affect it as well?
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The whole ceiling if installed correctly will flex on the bars and therefore absorb vibration/sound lights mounted should flex within ceiling and unless you have soundproofed walls as well then noise leakage through any openings i.e. Light fittings would be less I think than transferred through walls. You are reducing noise not eliminating it again there are systems for lights and door frames/doors etc all transfer noise to a degree.
 
A.plasterer said:
The whole ceiling if installed correctly will flex on the bars and therefore absorb vibration/sound lights mounted should flex within ceiling and unless you have soundproofed walls as well then noise leakage through any openings i.e. Light fittings would be less I think than transferred through walls. You are reducing noise not eliminating it again there are systems for lights and door frames/doors etc all transfer noise to a degree.
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Some good points there also worth mentioning if someone is thinking of soundproofing a wall on a semi detached house don't just think throwing up a stud wall with insulation and sound block will block say the t.v noise from the neighbouring house sound travels up and over it straight by passing the wall .. The ceiling defo needs to be done as well to get maximum sound block tbh I learnt the hard way on these there is more to blocking that sound than just boards.
 
When these big companies spec the acoustic reduction they only spec for the system as a whole,and apparently even if you double boarded it the extra layer of board won't actually keep that much extra noise out sounds mad to me but this was from Bg technical advice bloke
 
A.plasterer said:
Main issue as you will know I'm sure is not to accidentally fix the flexible part of the bar to any batten or metal /wood stud hence yes creating a static point .
Any boards or insulation again as long as not touching any edges of walls (unless also insulated for sound)so again edges to walls or pillars to be sealed with mastic to create flexible seal not transferring vibration ( noise).
I'm sure spec on ceilings is bars all running in one direction bar the last inverted. Maybe check on that as was 2 yrs ago since last one I did.
All info is found online.
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Not many know about the sealant but it's spec for all systems in the white book it's a little green dot and gets over looked it has to be done because of quality insurance and what they like to see is it around the system not underneath it again cos of quality assurance comes round and they don't see it they will ask you to take it up if you say it's underneath more of a get out clause than anything in my opinion
 
An update on this, those bars are a fking nightmare to screw into. The boards being heavy make it hard work and using course thread screws aren't helping me
 
When I did my place I made the loft room as sound proof as I could because I watch TV late up there and also work till the early hours and am often recording videos or editing them so being able to do that while jane sleeps in the room below is good.

Also when the time comes and we want kids I need to be able to shut the door and have some peace and quiet...

We used the knauf stuff ad spent about £5k but had been worth it

Sent from my SM-N910F using Tapatalk
 
Danny said:
When I did my place I made the loft room as sound proof as I could because I watch TV late up there and also work till the early hours and am often recording videos or editing them so being able to do that while jane sleeps in the room below is good.

Also when the time comes and we want kids I need to be able to shut the door and have some peace and quiet...

We used the knauf stuff ad spent about £5k but had been worth it

Sent from my SM-N910F using Tapatalk
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Was you watching them how to videos on plastering Dan?
 
stuart23 said:
An update on this, those bars are a fking nightmare to screw into. The boards being heavy make it hard work and using course thread screws aren't helping me
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Bg have changed there screws now to one screw does all they have got rid of timber screws and a few sizes maybe get a box of the size you require could make it easier
 
Pagey said:
Bg have changed there screws now to one screw does all they have got rid of timber screws and a few sizes maybe get a box of the size you require could make it easier
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For first board it's 25mm so you don't screw into joists by mistake but because the bars only have a fixing one side if you screw too close to other side the bar lifts and the screw doesn't bite. If you put pressure on and screw fast once it does bite it disappears through the board lol
 
stuart23 said:
For first board it's 25mm so you don't screw into joists by mistake but because the bars only have a fixing one side if you screw too close to other side the bar lifts and the screw doesn't bite. If you put pressure on and screw fast once it does bite it disappears through the board lol
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You doing on your own?
 
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