[Captain Ted]

I have just been given the go-ahead for building my extension, encorporating a dedicated cinema room.
I shall start a thread with piccies soon when I start as I am going for it in a serious way.

Before I start, I am soundproofing the walls with foam backed plasterboard and the door will be a firedoor with magnetic seals (still open to suggestions),

but what is the best way to soundproof the ceiling?

(It's on the ground floor and bedroom above)

Thanks,
Ted.

[albriscoe]

Hi Ted

I would first of all double board the ceiling, not tried the acoustic boards but have heard that they are ok.

The ceiling void I would fill with acoustic wadding but don`t cram it in so its all packed tight as loose fill is suppose to be better making sure all the void is filled well I`ve read.

Not used green glue either mate so maybe others who have might comment.

looking forward to the pics made and good luck

Al

[Captain Ted]

Hi Al

What's green glue?

Never thought about double boarding....nice one!

While you are on, do you agree with the foam backed plasterboard for the walls?

Ted.

[bladster]

had the same issue myself, I think the dilemma is that you can shed out serious cash and there is no garuntee that it will do what it says on the packet.

I have gone for knauff mineral wool (75mm) and riser bars, and then plan to use two layers of 12.5mm acoustic platerboard.

I will do some simple tests but watch my thread as I will post anything and pics as I go along.

Enjoy

[monkeyboy69]

literally just done this myself and used
100mm accoustic rockwall

Acoustic mineral wool slabs UK - dense fibre matting DFM

and then went over the top with 12.5 mm accoustic plasterboard.

id read many things on here regarding double plasterboarding , false ceilings etc, but after talking to a few builders and plasterers who'd done this thing before theyd said they'd didnt noticed much difference between single and double boarding the ceiling and thr false ceiling option would have made the room too claustophopic being only 2.4 M high

I havent finished my room yet so i cant report on how effective my soution is but if its still a problem i'l probably attck it my layout rubber accoustic matting under the carpet upstairs.

[albriscoe]

Double boarding I think would be slightly better than a single acoustic board, also using the foam back boards for the wall is more for heat insulation rather than acoustic, but every little helps, maybe a cheaper better solution is out their mate.

I can`t help thinking that a good insulation wadding such as Knaufe filling the cavity but as I said not crammed in so its solid could be as good as anything.

Green glue is an adhesive to stick the boards together as far as I know Ted.

Does it work? I wouldn`t have a clue mate

but its not as good as the blue and yellow checked stuff

[RipMaster]

Is this stuff any good I wonder http://www.acoustiblok.com/ they seem to have some high calibre reference sites.

[deansocial]

doubleboarding does make a differance. Just done a load of studding with 2 layers od 15mm dbcheck and 25mm rockwool and they work well. Less joints are better as well so buy bigger boards were you can. Do you have room to put a seperate ceiling in lower down therefore decoupling from the top floor above. you can also use gyp plank to add mass between joists

[Captain Ted]

It looks like I shall:

1. Fill between joists with fibreglass (9" thick)
2. Fit resilient bars to joists.
3. double board with accoustic mat between them.

Walls will be similar but built in blockwork.

Thanks all.
Ted.

[albriscoe]

Originally Posted by Captain Ted

It looks like I shall:

1. Fill between joists with fibreglass (9" thick)
2. Fit resilient bars to joists.
3. double board with accoustic mat between them.

Walls will be similar but built in blockwork.

Thanks all.
Ted.

good on ya Ted

don`t forget the pics mate

[amioa]

double boarding has a dual function, it increases the mass, thereby lowering the resonance point, and stiffens the wall up, reducing any diaphramatic effects. Green Glue will damp the board, further improving the systems ability to transmit less. Acoustibloc and green glue do similar things, one comes in a big heavy roll, and one comes in a box thats easier to carry.