Sound proofing external facing stud wall behind a garage door

[alex889]

Hey guys, I'm building a stud wall behind my garage door (metal door) to use as a recording space and I'm wondering about the best materials to use to create a good sound barrier with good thermal performance too. I was thinking about using 4x2 to make the frame and on the side facing the garage door cover it with some high density material. I'm not sure if that could be OSB as it seems to be more resistant to humidity as well. Inside the wall I'm planning to add 90mm PIR insulation, and then on the inside 1 layer 15mm acoustic plasterboard with a layer of tecsound and then another 15mm layer pf acoustic plasterboard.



I'f anyone has any other suggestions about different materials I could use it would be great.

 

[RandomGrinch]

I'm not an expert, so feel free to ignore
But for a start, ditch the PIR. PIR has no sound insulation properties and can actually make matters worse.
A better choice would be Rockwool sound insulation slabs:
https://www.wickes.co.uk/Rockwool-Sound-Insulation-Slab---100-x-400mm-x-1-2m/p/148842
The art of sound insulation can be a complex one with the idea being to de-couple different surfaces.
This will include the other walls of the garage and if possible, the floor and ceiling.
You might also consider the use of anechoic sound panels and a vapour barrier on your stud wall.

 

[Tigercubrider]

As above

Isolation is important.
Build a 4x2 frame and DO NOT secure it to the concrete.
Get 1" thick neoprene /rubber which can be glued to the wall/floor and if you must, screw the timber to the neoprene.
Use two types of acoustic rock wool in the void, with a gap.

Probably best to apply the first plasterboard internal layer.
That way you can fill the seams from each side.
Use two layers of plasterboard, staggered by 50% so no seams line up.

On the external face, do the same.
You could also add the OSB with a slight gap and neoprene if you can.

It's all about being airtight, sealing tiny gaps and mixing different materials and thicknesses.
This prevents transmission.
The neoprene absorbs transmission between the new build and outer structure.

 

[^woody^]

That's a bad specification for sound proofing. It's just a basic timber frame wall, like a loft dormer!

You need dense materials and isolation of the frame.

But in practical terms, the wall behind the garage door does not need to be any better than the other three walls.

 

[alex889]

I'm not an expert, so feel free to ignore
But for a start, ditch the PIR. PIR has no sound insulation properties and can actually make matters worse.
A better choice would be Rockwool sound insulation slabs:
https://www.wickes.co.uk/Rockwool-Sound-Insulation-Slab---100-x-400mm-x-1-2m/p/148842
The art of sound insulation can be a complex one with the idea being to de-couple different surfaces.
This will include the other walls of the garage and if possible, the floor and ceiling.
You might also consider the use of anechoic sound panels and a vapour barrier on your stud wall.

I'm using PIR for thermal insulation, not for sound. The idea is to create a good thermal and acoustic barrier mixing materials. That is why I was thinking about a thick tong and groove OSB board on the outer side of this stud wall (it will face the metal garage door, about 10cm gap between) or even chipboard, but I guess that may not be the best solution as it will be slightly exposed to the elements. maybe cover it with a breathable membrane? I'm covering all the perimeter of the garage door with expanding foam tape from these guys Expanding Foam Tape | EXP6 Pre-Compressed Joint Sealing Tape Next Day as they claim it wind and water proof if using the right compression rate. I'm still leaving gaps at the top for ventilation for any moisture trapped in between the garage door and the stud wall

I was looking at the rockwall product more for internal studwork than external due to its lack of good thermal performance compared to PIR boards. I could use it as another layer after the PIR board, but I'm wondering if I can achieve better results just by adding thick OSB + 2x layers of 15mm acoustic plasterboard with tecsound in between. The last resort would be to build another stud wall a bit thinner with perhaps 2 layers of plasterboard and rockwoll in between, but that may start to take a lot of space.

anechoic sound panels are just for acoustic treatment to make the sound better inside the room, I'm planning to use proper panels in place, but that is for when everything is plastered.

I'm definitely going for a vapour barrier.

As above

Isolation is important.
Build a 4x2 frame and DO NOT secure it to the concrete.
Get 1" thick neoprene /rubber which can be glued to the wall/floor and if you must, screw the timber to the neoprene.
Use two types of acoustic rock wool in the void, with a gap.

Probably best to apply the first plasterboard internal layer.
That way you can fill the seams from each side.
Use two layers of plasterboard, staggered by 50% so no seams line up.

On the external face, do the same.
You could also add the OSB with a slight gap and neoprene if you can.

It's all about being airtight, sealing tiny gaps and mixing different materials and thicknesses.
This prevents transmission.
The neoprene absorbs transmission between the new build and outer structure.

I've built a floor over the concrete with a DPM layer and a frame made of 4x2s filled with 90mm PIR boards and covered with 22mm T&G chipboard. Do you think the neoprene can take the vertical load of the stud wall (2.4m wide and 2.5m tall with plaster and insulation) without being compressed too much and lose its properties? Where would you get neoprene of this thickness? I'm just finding 5mm max, I could stack them but just checking if you know where to get it from.

I'm struggling to see how I can get the OSB fixed to the frame with using the neoprene glued, it will need some form of screw fixing due to the weight I guess, plus I'll need to assemble to stud work on the floor and lift it up in place as the garage door opens upwards (which I'm going to block) so a bit of a tricky situation. I wonder how much sound will the fixing screws of the OSB transfer to the frame if using neoprene in between, what do you think?

That's a bad specification for sound proofing. It's just a basic timber frame wall, like a loft dormer!

You need dense materials and isolation of the frame.

But in practical terms, the wall behind the garage door does not need to be any better than the other three walls.

The other 3 walls are fine, it is between 2 other garages so I'm just trying to mitigate the sound coming from the garage door and the ceiling, all other directions should be okay (in theory)

 

[SFK]

True sound proofing is near impossible and very expensive to do well.

Stud wall with interlocked studs (ie two sets of studs, every other stud slight Infront of next. That way plasterboard on one side of wall is not connected to the plasterboard on other side of wall.
Lookup "staggered stud wall"
https://www.google.com/search?q=sta...motorola-rev2&sourceid=chrome-mobile&ie=UTF-8

Ensure no gaps. Fill all gaps.

Sound absorbing insulation between plasterboard (this will also thermally insulate - but not as well as PIR).
https://www.wickes.co.uk/Rockwool-S...QVPwk_81dA3c3MuGeRoaAkB1EALw_wcB&gclsrc=aw.ds


Heavy sound absorbing plasterboard, not normal plasterboard. If you have space double up boards overlapping seams.
https://www.wickes.co.uk/Knauf-Soun...aTnGKmddUxvyMoLC6IEaAkLIEALw_wcB&gclsrc=aw.ds

Green glue (I have never used)
https://www.google.com/search?q=gre...motorola-rev2&sourceid=chrome-mobile&ie=UTF-8

Use a fire door not a normal door. If not practical, go for heaviest door you can use.

Read more: https://www.diynot.com/diy/threads/soundproofing-to-downstairs-wc.570939/#ixzz770iLL8ZM

Also, if it is a recording space to impove the recordinhg itself I think there are considerations to be made in advance on optimising the shape of the actual room.
And the hanging of sound absorbing materials.

 

[Tigercubrider]

yes decent neoprene or rubber will take the load
Last time we bought some was from Hills Rubber in Reading
same as
https://shop.deltarubber.co.uk/rubb...rubber-strip/solid-neoprene-rubber-strip.html

if you are serious about stopping sound, ideally the floor would have been better floating on RW1 or 2 which is a pretty dense fibre.
Then glued T&G flooring edge to edge but no spikes or glue to join the insulation and floor covering.
Don't allow any contact with the edges.

 

[alex889]

True sound proofing is near impossible and very expensive to do well.

Stud wall with interlocked studs (ie two sets of studs, every other stud slight Infront of next. That way plasterboard on one side of wall is not connected to the plasterboard on other side of wall.
Lookup "staggered stud wall"
https://www.google.com/search?q=sta...motorola-rev2&sourceid=chrome-mobile&ie=UTF-8

Ensure no gaps. Fill all gaps.

Sound absorbing insulation between plasterboard (this will also thermally insulate - but not as well as PIR).
https://www.wickes.co.uk/Rockwool-S...QVPwk_81dA3c3MuGeRoaAkB1EALw_wcB&gclsrc=aw.ds


Heavy sound absorbing plasterboard, not normal plasterboard. If you have space double up boards overlapping seams.
https://www.wickes.co.uk/Knauf-Soun...aTnGKmddUxvyMoLC6IEaAkLIEALw_wcB&gclsrc=aw.ds

Green glue (I have never used)
https://www.google.com/search?q=gre...motorola-rev2&sourceid=chrome-mobile&ie=UTF-8

Use a fire door not a normal door. If not practical, go for heaviest door you can use.

Read more: https://www.diynot.com/diy/threads/soundproofing-to-downstairs-wc.570939/#ixzz770iLL8ZM

Also, if it is a recording space to impove the recordinhg itself I think there are considerations to be made in advance on optimising the shape of the actual room.
And the hanging of sound absorbing materials.

One of the internal walls will be staggered to avoid sound transmission between the two as it will be an easy win, around the perimeter of the garage becomes difficult due to the space it takes. I decided to buy rockwoll RWA45 which is 45kg per m3 to use in the stud walls that need sound proofing, it will be between 2 layers of 15mm high acoustic plasterboards which will be separated from the stud frame by 5mm cork layer, a 25mm PIR board, then on the internal side the plaster will have a layer of tecsound s100 and another 15mm layer of plasterboard.

I'm planning to use a FD30 rated door, maybe add a layer of tecsound to it and a layer of 15mm plywood.

Internally I'll add some acoustic panels to improve the sound reflection, perhaps I may make these myself as well

yes decent neoprene or rubber will take the load
Last time we bought some was from Hills Rubber in Reading
same as
https://shop.deltarubber.co.uk/rubb...rubber-strip/solid-neoprene-rubber-strip.html

if you are serious about stopping sound, ideally the floor would have been better floating on RW1 or 2 which is a pretty dense fibre.
Then glued T&G flooring edge to edge but no spikes or glue to join the insulation and floor covering.
Don't allow any contact with the edges.

Thanks, I checked it out but ended up going with cork as I got a 5m roll 1m wide of 5mm for £40

 

[Tigercubrider]

Not sure cork is ideal but depends on budget and how far you are prepared to go.
A mate's studio in the west end (with a massive budget!) sits on truck coil springs which are mounted on rubber and different timbers to stop transmission by contact

One tip for improved acoustics is to angle your dividing wall so that you don't' have four right angle corners.
It helps with sound reflection. A cube is a terrible shape, a rectangle is better and a non square shape better still.

Don't forget the windows and if you can, add laminated glass to be a second/third layer.
Angle it so it's not parallel to the existing glass.
The different layers should be different thicknesses, the planes should be angled both for acoustic reasons and to stop the outer glass resonating like a second drum skin so allowing sound leakage.