Insulation Of Condo Walls And Ceiling To Make It Quiet?

[nycboy57]

I noticed I put in Bkk forum and got no replies, so was hoping this is the appropriate location for asking

for help for this topic? Can anyone help with installation of insulation. The ceilings are hollow about a foot high, they have srpinkler system inside and the lighting is in the ceiling. When I look inside the ceiling at the air conditioning vent, i see that the walls along the edges are wide open and cracked and someone suggested a system that can shoot an expanding type of liquid insulation at certain areas of the ceiling. I am located in Bkk. Can someone recommend or do? I have purchased an English language yellow pages and looked under insulationation and found many but no one so far is willing to do. THe former owner of this condo had some do a wall with insulation but they had an armoire at the end and the construction worker did not finish it or fix the electric plugs correctly, when we tried to get him to come back and finish the wall and do the ceilings he said he was in Chang Mai and when he returned would come over but that was months ago. so I do smell when they cook next door and hear them when they have tv or talk. Please help. Thanks in advance.

[klikster]

I noticed I put in Bkk forum and got no replies, so was hoping this is the appropriate location for asking

for help for this topic? Can anyone help with installation of insulation. The ceilings are hollow about a foot high, they have srpinkler system inside and the lighting is in the ceiling. When I look inside the ceiling at the air conditioning vent, i see that the walls along the edges are wide open and cracked and someone suggested a system that can shoot an expanding type of liquid insulation at certain areas of the ceiling. I am located in Bkk. Can someone recommend or do? I have purchased an English language yellow pages and looked under insulationation and found many but no one so far is willing to do. THe former owner of this condo had some do a wall with insulation but they had an armoire at the end and the construction worker did not finish it or fix the electric plugs correctly, when we tried to get him to come back and finish the wall and do the ceilings he said he was in Chang Mai and when he returned would come over but that was months ago. so I do smell when they cook next door and hear them when they have tv or talk. Please help. Thanks in advance.

I will answer some of this in generalities. Two types of sound attenuation influence noise. (1) Stopping the transmission of sound and (2) preventing build up from reverberation.

The lower the frequency of sound, the more difficult it is to attenuate.

As I understand, you want to attenuate the sound entering from outside.

Generally, dense, limp barriers reduce sound transmission. Steel is dense, but not limp. So at certain frequencies, it "rings". Steel with a "visco-elastic" material applied tends not to ring. Sheet lead is an excellent material as it is dense, limp and easy to fold around uneven surfaces and fittings. Not sure about Thailand, but an acoustic lead is available in thin sheets on rolls in the west.

Wallboard is probably the best material for your situation. A double layer with offset seams spaced several inches from another double layer should give somewhere around 40-60 db. Slightly better with offset studs.

Spaces around sound barriers will render even the best barrier system nearly ineffective. A 10% space can reduce the attenuation of a -60 db wall to about 6 db. Even small cracks and openings should be sealed on both sides with an elastic caulking.

Porous materials like fiberglass and open cell foams have very poor attenuation properties. They do tend to attenuate sound within a space by shearing the sound wave and reducing reverberation.

If sound is traveling through an A/C vent duct, a silencer can be somewhat effective if properly designed and installed. Generally, this is difficult and expensive.

For reducing transmission through a wall, one possible cure is to build a false wall (double wallboard with seams offset and taped), set out on furring strips as far as practical from the existing wall.

[nycboy57]

I noticed I put in Bkk forum and got no replies, so was hoping this is the appropriate location for asking

for help for this topic? Can anyone help with installation of insulation. The ceilings are hollow about a foot high, they have srpinkler system inside and the lighting is in the ceiling. When I look inside the ceiling at the air conditioning vent, i see that the walls along the edges are wide open and cracked and someone suggested a system that can shoot an expanding type of liquid insulation at certain areas of the ceiling. I am located in Bkk. Can someone recommend or do? I have purchased an English language yellow pages and looked under insulationation and found many but no one so far is willing to do. THe former owner of this condo had some do a wall with insulation but they had an armoire at the end and the construction worker did not finish it or fix the electric plugs correctly, when we tried to get him to come back and finish the wall and do the ceilings he said he was in Chang Mai and when he returned would come over but that was months ago. so I do smell when they cook next door and hear them when they have tv or talk. Please help. Thanks in advance.

I will answer some of this in generalities. Two types of sound attenuation influence noise. (1) Stopping the transmission of sound and (2) preventing build up from reverberation.

The lower the frequency of sound, the more difficult it is to attenuate.

As I understand, you want to attenuate the sound entering from outside.

Generally, dense, limp barriers reduce sound transmission. Steel is dense, but not limp. So at certain frequencies, it "rings". Steel with a "visco-elastic" material applied tends not to ring. Sheet lead is an excellent material as it is dense, limp and easy to fold around uneven surfaces and fittings. Not sure about Thailand, but an acoustic lead is available in thin sheets on rolls in the west.

Wallboard is probably the best material for your situation. A double layer with offset seams spaced several inches from another double layer should give somewhere around 40-60 db. Slightly better with offset studs.

Spaces around sound barriers will render even the best barrier system nearly ineffective. A 10% space can reduce the attenuation of a -60 db wall to about 6 db. Even small cracks and openings should be sealed on both sides with an elastic caulking.

Porous materials like fiberglass and open cell foams have very poor attenuation properties. They do tend to attenuate sound within a space by shearing the sound wave and reducing reverberation.

If sound is traveling through an A/C vent duct, a silencer can be somewhat effective if properly designed and installed. Generally, this is difficult and expensive.

For reducing transmission through a wall, one possible cure is to build a false wall (double wallboard with seams offset and taped), set out on furring strips as far as practical from the existing wall.

Thank you for that information, my problem is getting someone to efficiently do this job for me here in Bangkok. I was told by some contractors who came here that the wall is useless the problem is the hollow ceiling and the cracks and spaces in that ceiling. That is why I am asking for someone to do this job, get some estimates and see how that works in terms of noise coming through and smells from cooking next apartments. This is the third apartment I have lived in this Condo and first one I owned and it is with the highest ceilings and largest apartment here.

[klikster]

I noticed I put in Bkk forum and got no replies, so was hoping this is the appropriate location for asking

for help for this topic? Can anyone help with installation of insulation. The ceilings are hollow about a foot high, they have srpinkler system inside and the lighting is in the ceiling. When I look inside the ceiling at the air conditioning vent, i see that the walls along the edges are wide open and cracked and someone suggested a system that can shoot an expanding type of liquid insulation at certain areas of the ceiling. I am located in Bkk. Can someone recommend or do? I have purchased an English language yellow pages and looked under insulationation and found many but no one so far is willing to do. THe former owner of this condo had some do a wall with insulation but they had an armoire at the end and the construction worker did not finish it or fix the electric plugs correctly, when we tried to get him to come back and finish the wall and do the ceilings he said he was in Chang Mai and when he returned would come over but that was months ago. so I do smell when they cook next door and hear them when they have tv or talk. Please help. Thanks in advance.

I will answer some of this in generalities. Two types of sound attenuation influence noise. (1) Stopping the transmission of sound and (2) preventing build up from reverberation.

The lower the frequency of sound, the more difficult it is to attenuate.

As I understand, you want to attenuate the sound entering from outside.

Generally, dense, limp barriers reduce sound transmission. Steel is dense, but not limp. So at certain frequencies, it "rings". Steel with a "visco-elastic" material applied tends not to ring. Sheet lead is an excellent material as it is dense, limp and easy to fold around uneven surfaces and fittings. Not sure about Thailand, but an acoustic lead is available in thin sheets on rolls in the west.

Wallboard is probably the best material for your situation. A double layer with offset seams spaced several inches from another double layer should give somewhere around 40-60 db. Slightly better with offset studs.

Spaces around sound barriers will render even the best barrier system nearly ineffective. A 10% space can reduce the attenuation of a -60 db wall to about 6 db. Even small cracks and openings should be sealed on both sides with an elastic caulking.

Porous materials like fiberglass and open cell foams have very poor attenuation properties. They do tend to attenuate sound within a space by shearing the sound wave and reducing reverberation.

If sound is traveling through an A/C vent duct, a silencer can be somewhat effective if properly designed and installed. Generally, this is difficult and expensive.

For reducing transmission through a wall, one possible cure is to build a false wall (double wallboard with seams offset and taped), set out on furring strips as far as practical from the existing wall.

Thank you for that information, my problem is getting someone to efficiently do this job for me here in Bangkok. I was told by some contractors who came here that the wall is useless the problem is the hollow ceiling and the cracks and spaces in that ceiling. That is why I am asking for someone to do this job, get some estimates and see how that works in terms of noise coming through and smells from cooking next apartments. This is the third apartment I have lived in this Condo and first one I owned and it is with the highest ceilings and largest apartment here.

Well, basically .. read my post again .. then get someone to build you a second "ceiling" that reduces sound transmission. But you also talked about walls. I suggest that you prepare to spend some serious time and $$$ or learn to live with the environment. There are no simple, easy, magic cures for these types of problems.

You might .. or might not .. find someone to lay a layer of lead sheet above a dropped ceiling.

"Sheet lead is an excellent material as it is dense, limp and easy to fold around uneven surfaces and fittings. Not sure about Thailand, but an acoustic lead is available in thin sheets on rolls in the west."

[wpcoe]

I've considered moving to another area which has nothing but townhouses: you know, the ubiquitous Thai townhouses with nothing but rendered red-brick walls between the dwellings, electrical wiring on the surface, etc. My main concern has been the noise from neighbors on adjacent sides, and I had wondered about putting a second wall on the common walls (possibly just in the bedrooms) using vertical wood studs (the equivalent of 2"x4"), and putting gypsum wallboard on the interior sides. Would that (an empty 4" cavity) noticeably reduce the noise? Would putting fiberglass insulation in the cavity make more of a difference?

One problem I have with such a construct is that the standard townhouse is not all that wide to begin with, and to take another 9" away would be noticeable. With that in mind, what about using the equivalent of a 2"x2" stud and having a shallower cavity?

[klikster]

I've considered moving to another area which has nothing but townhouses: you know, the ubiquitous Thai townhouses with nothing but rendered red-brick walls between the dwellings, electrical wiring on the surface, etc. My main concern has been the noise from neighbors on adjacent sides, and I had wondered about putting a second wall on the common walls (possibly just in the bedrooms) using vertical wood studs (the equivalent of 2"x4"), and putting gypsum wallboard on the interior sides. Would that (an empty 4" cavity) noticeably reduce the noise? Would putting fiberglass insulation in the cavity make more of a difference?

One problem I have with such a construct is that the standard townhouse is not all that wide to begin with, and to take another 9" away would be noticeable. With that in mind, what about using the equivalent of a 2"x2" stud and having a shallower cavity?

That's a tough call. Some of the noise on higher floors come from gaps / spaces above the wall .. between wall and roof. I would assume that building / closing that space could mean getting permission from neighbors?

For the false walls, Much will depend on how the sound enters the living space. Sound gets transmitted through dense materials such as walls, floor and ceilings; from which it essentially "radiates" as a pressure wave. Building false walls will only reduce the sound level from the wall.

If you are going to build a false wall, decouplingit from the existing wall is important, i.e., staggered studs. And sealing any gaps is paramount.

All that being said, I would never try to tackle a project like you describe. I lived in a townhouse once and would never consider another.

[wpcoe]

Thanks for the feedback. I think the townhouses in the area I'm considering *do* have a "common area" under a vaulted (is that the term?) roof. The only townhouse I've lived in before, simply had flat concrete roofs with no open space above the ceilings. (i.e. The top floor was a blazingly hot place to be on a sunny day.)

All that being said, I would never try to tackle a project like you describe. I lived in a townhouse once and would never consider another.

Yeah, having lived in a townhouse once, I'm nervous against doing it again, as well, hence my questions about how to soundproof one.

[trogers]

Thanks for the feedback. I think the townhouses in the area I'm considering *do* have a "common area" under a vaulted (is that the term?) roof. The only townhouse I've lived in before, simply had flat concrete roofs with no open space above the ceilings. (i.e. The top floor was a blazingly hot place to be on a sunny day.)

All that being said, I would never try to tackle a project like you describe. I lived in a townhouse once and would never consider another.

Yeah, having lived in a townhouse once, I'm nervous against doing it again, as well, hence my questions about how to soundproof one.

Before spending money on just sealing cracks above the common walls, find out the type of material the walls are made from. If it is cheap single layer thin hollow block, you will need to build a second layer (probably with 12mm thick Viva board) with a 2-inch cavity and filled up with Rockwool to cut down sound penetration through the existing wall.

This would mean taking down the ceiling to get the work done properly. Cracks above the solid walls can be filled with white packing foam and sealed with silicone, prior to building the 2nd wall.

Any interior contractor who can build lightweight partition walls and suspended ceiling can get the job done.

[klikster]

Mineral wool and fiberglass do little to reduce the transmission of sound. Used between 2 dense materials, they pretty much prevent standing waves and little else.

Depending on the size of the "cracks" / gap between the wall and roof (some measure in feet rather than inches) I don't recommend "packing foam" .. polystyrene. It is flammable and has extremely low density .. which is the opposite of what is needed to reduce sound transmission.

Any interior contractor who can build lightweight partition walls and suspended ceiling can get the job done.

Assuming he knows what he is doing.

Edited June 24, 2010 by klikster

[trogers]

Mineral wool and fiberglass do little to reduce the transmission of sound. Used between 2 dense materials, they pretty much prevent standing waves and little else.

Depending on the size of the "cracks" / gap between the wall and roof (some measure in feet rather than inches) I don't recommend "packing foam" .. polystyrene. It is flammable and has extremely low density .. which is the opposite of what is needed to reduce sound transmission.

Any interior contractor who can build lightweight partition walls and suspended ceiling can get the job done.

Assuming he knows what he is doing.

Viva board is not a dense material and mineral wool (similar to those used to cover air-con ducts) reduces reverberation.

As the party (common) wall separates two condo units, the cracks at the top of the wall will not be large, probably not more than 1.2cm, due to deflection of the structural floor support. Fire issue is not significant as the Viva boards have to be burnt through before the packing foam is affected.

Edited June 25, 2010 by trogers

[klikster]

Mineral wool and fiberglass do little to reduce the transmission of sound. Used between 2 dense materials, they pretty much prevent standing waves and little else.

Depending on the size of the "cracks" / gap between the wall and roof (some measure in feet rather than inches) I don't recommend "packing foam" .. polystyrene. It is flammable and has extremely low density .. which is the opposite of what is needed to reduce sound transmission.

Any interior contractor who can build lightweight partition walls and suspended ceiling can get the job done.

Assuming he knows what he is doing.

Viva board is not a dense material and mineral wool (similar to those used to cover air-con ducts) reduces reverberation.

As the party (common) wall separates two condo units, the cracks at the top of the wall will not be large, probably not more than 1.2cm, due to deflection of the structural floor support. Fire issue is not significant as the Viva boards have to be burnt through before the packing foam is affected.

Viva board is not a dense material

Then it will do very little to attenuate sound transmission .. but from what I can see on the web, I would call it a dense material. It's a composite of wood and concrete.

If I were considering an interior wall for sound reduction, it would be double 1/2" or 5/8" gypsum board with offset seams sealed and taped.

As to mineral wool will reduce reverberation, but only withing the space between the existing wall and the newly built wall.

As for the gaps above walls, above the ceiling .. between wall and roof, I have seen half-meter spaces.

I doubt we are on the same wavelength so I will bow out of this conversation.

[trogers]

Then it will do very little to attenuate sound transmission .. but from what I can see on the web, I would call it a dense material. It's a composite of wood and concrete.

If I were considering an interior wall for sound reduction, it would be double 1/2" or 5/8" gypsum board with offset seams sealed and taped.

As to mineral wool will reduce reverberation, but only withing the space between the existing wall and the newly built wall.

As for the gaps above walls, above the ceiling .. between wall and roof, I have seen half-meter spaces.

I doubt we are on the same wavelength so I will bow out of this conversation.

OP mentioned a condo unit, and not a house with pitched roof.

Solid wall will be built from concrete floor and abut the soffit of the concrete slab above. The same goes with building the layer of Viva board and mineral wool insulation. Suspended ceiling should abut to the Viva board layer.

[klikster]

OP mentioned a condo unit, and not a house with pitched roof.

But another poster .. the one to whom I directed my reply .. asked about a townhouse.

Maybe if you had read the entire thread ..

[trogers]

OP mentioned a condo unit, and not a house with pitched roof.

But another poster .. the one to whom I directed my reply .. asked about a townhouse.

Maybe if you had read the entire thread ..

Party walls of townhouses should be built right up to the roof structure for two main reasons - to prevent fire spread and break-in between house units. If the party wall is built right, there should not be excessive sound transmissions over this wall.

[aussiebebe]

OP mentioned a condo unit, and not a house with pitched roof.

But another poster .. the one to whom I directed my reply .. asked about a townhouse.

Maybe if you had read the entire thread ..

Hi klikste, you seem highly knowledgeable about sound-proofing and insulation, which is an issue for me at the moment where I live. I always presumed foam was good, so I've learnt something by reading your posts. Out of interest, you wrote you'd never again consider a townhouse - is this due to the noise from neighbours? and, guessing that you prefer either detached houses or condominiums, if you were choosing a condo to live in, what are things you'd check or look for to try to minimise the possibility of sound/noise being an issue?

[klikster]

Hi klikste, you seem highly knowledgeable about sound-proofing and insulation, which is an issue for me at the moment where I live. I always presumed foam was good, so I've learnt something by reading your posts. Out of interest, you wrote you'd never again consider a townhouse - is this due to the noise from neighbours? and, guessing that you prefer either detached houses or condominiums, if you were choosing a condo to live in, what are things you'd check or look for to try to minimise the possibility of sound/noise being an issue?

Foam

Generally, foam is a big negatory for me. When most foams burn, they give off toxic fumes .. which tend to incapacitate people, and said people end up dead.

Townhouses vs Condos

For me, townhouses have a number of negatives. I'm approaching the end of 7 decades on this earth, so stairs are not something I look forward to. Also, my feet don't fit standard Thai stair dimensions.

Privacy and parking difficulties are other issues with townhouses.

Having spent a number of years doing industrial noise control, I have probably been sensitized to noise. So I look for exceptionally quiet places to live.

As to preferring condos vs. townhouses, I would usually say "condo".

- I think there will be fewer folks living in the condo next door than in the townhouse next door.

- You never know who or what will suddenly show up in the townhouse next door .. i.e., karaoke, motorcycle shop, etc.

- A well-managed condo will be able to exert more influence on residents, especially renters, than .. townhouses.

- If you go for a townhouse, get an end unit .. and never a unit at the dead-end of a soi (parking).

There are folks here with much more expertise in evaluating condo living condition than me, so maybe they will add to this thread. Best is to rent for awhile. As close as possible to the unit you are considering. Also, ask the residents.

- Who lives there?

- What is built nearby?

- Soi dog population?

- Get a a builder who is truly knowledgeable about noise to evaluate the unit.

[trogers]

Hi klikste, you seem highly knowledgeable about sound-proofing and insulation, which is an issue for me at the moment where I live. I always presumed foam was good, so I've learnt something by reading your posts. Out of interest, you wrote you'd never again consider a townhouse - is this due to the noise from neighbours? and, guessing that you prefer either detached houses or condominiums, if you were choosing a condo to live in, what are things you'd check or look for to try to minimise the possibility of sound/noise being an issue?

Foam

Generally, foam is a big negatory for me. When most foams burn, they give off toxic fumes .. which tend to incapacitate people, and said people end up dead.

Townhouses vs Condos

For me, townhouses have a number of negatives. I'm approaching the end of 7 decades on this earth, so stairs are not something I look forward to. Also, my feet don't fit standard Thai stair dimensions.

Privacy and parking difficulties are other issues with townhouses.

Having spent a number of years doing industrial noise control, I have probably been sensitized to noise. So I look for exceptionally quiet places to live.

As to preferring condos vs. townhouses, I would usually say "condo".

- I think there will be fewer folks living in the condo next door than in the townhouse next door.

- You never know who or what will suddenly show up in the townhouse next door .. i.e., karaoke, motorcycle shop, etc.

- A well-managed condo will be able to exert more influence on residents, especially renters, than .. townhouses.

- If you go for a townhouse, get an end unit .. and never a unit at the dead-end of a soi (parking).

There are folks here with much more expertise in evaluating condo living condition than me, so maybe they will add to this thread. Best is to rent for awhile. As close as possible to the unit you are considering. Also, ask the residents.

- Who lives there?

- What is built nearby?

- Soi dog population?

- Get a a builder who is truly knowledgeable about noise to evaluate the unit.

Two points on sound and privacy to look out for when choosing a condo unit are:

- the quality and sound insulation of the main entrance door

- the location of the unit of that floor and the number of people who will walk pass your entrance door.

I have come across developers spending on expensive finish to an entrance door, but cut cost by giving you a door panel that is hollow. In addition, the gap between the door panel and the floor finish should not be more than 5mm. Changing the door panel by yourself is not an option as you need to gather 50% approving votes from other owners.

If the condo unit is near to the lift lobby along a long corridor, you will suffer more people walking pass your entrance door.

[cheshiremusicman]

I've considered moving to another area which has nothing but townhouses: you know, the ubiquitous Thai townhouses with nothing but rendered red-brick walls between the dwellings, electrical wiring on the surface, etc. My main concern has been the noise from neighbors on adjacent sides, and I had wondered about putting a second wall on the common walls (possibly just in the bedrooms) using vertical wood studs (the equivalent of 2"x4"), and putting gypsum wallboard on the interior sides. Would that (an empty 4" cavity) noticeably reduce the noise? Would putting fiberglass insulation in the cavity make more of a difference?

One problem I have with such a construct is that the standard townhouse is not all that wide to begin with, and to take another 9" away would be noticeable. With that in mind, what about using the equivalent of a 2"x2" stud and having a shallower cavity?

That's a tough call. Some of the noise on higher floors come from gaps / spaces above the wall .. between wall and roof. I would assume that building / closing that space could mean getting permission from neighbors?

For the false walls, Much will depend on how the sound enters the living space. Sound gets transmitted through dense materials such as walls, floor and ceilings; from which it essentially "radiates" as a pressure wave. Building false walls will only reduce the sound level from the wall.

If you are going to build a false wall, decouplingit from the existing wall is important, i.e., staggered studs. And sealing any gaps is paramount.

All that being said, I would never try to tackle a project like you describe. I lived in a townhouse once and would never consider another.

I totally concur. I lived in a semi-detached house in the UK and the 'noise transmission' between the two houses was bad, so much so, that you could distinctly make out conversations 'next door' and my neighbours were not particularly loud people. The biggest problem, as already said, is because certain structural materials 'transmit rather than attenuate sound'. One would imagine that a solid brick wall with 'real plaster render on both sides' would be a reasonable noise barrier, but no, the problem was that the 'brick wall' was almost made up entirely of what I would describe as 'engineering brick' - being blue in places and EXTREMELY hard - I know because I had to cut out 'full depth boxes' for a rewire of the house and it was almost impossible to drill even with a very good hammer drill and tungsten tipped drills. Lead lining apart, I don't think that you will solve the problem to a satisfactory degree and you will end up spending a lot of money for very little return. 'Lead curtaining material' was available in the UK, but I doubt very much if you can obtain this in Thailand - this I believe is the only way that you would achieve any acceptable results. Sorry, but there are no simple solutions to your problem that I have heard of - if you find one out then I am sure that you could make a fortune back in the UK and elsewhere helping people like yourself that are plagued with noise.

[aussiebebe]

Thanks 'klikster' and 'trogers' for those helpful pieces of advice about noise and choosing places. Good advice. Cheers

Edited July 2, 2010 by aussiebebe

[powderpuff]

The company that sprays foam are located in Pattaya. I think the owners son was named Chris that came to my house in Bangkok & meausred & quoted me a price.

I addition to reducing heat it also made the roof tiles pretty much water tite.

I no longer have the details on how to contact them.

[powderpuff]

wpcoe. Today in Thailand 2x4's are made of metal. You could lay them sideways & then you lose 2 inch plus the thickness of the gypsum board +/- 1/2 inch. Yes fiberglass would be excellent as insulation.

[wpcoe]

Party walls of townhouses should be built right up to the roof structure for two main reasons - to prevent fire spread and break-in between house units. If the party wall is built right, there should not be excessive sound transmissions over this wall.

*Should* be, but I've seen plenty of townhouses where they have a big open "attic space" above the units, and there's nary a wall or divider in it from one end of the block of townhouses to the other end...

And, some townhouses I looked at which had such an open arrangement above the units, had simple ceiling tiles as the upper floor ceiling. Ceiling tiles which could *easily* be removed from above in the privacy of the attic space for quick and quiet kamoey-entry access!

[wpcoe]

wpcoe. Today in Thailand 2x4's are made of metal. You could lay them sideways & then you lose 2 inch plus the thickness of the gypsum board +/- 1/2 inch. Yes fiberglass would be excellent as insulation.

Duh. I never considered that. Or, actually I guess a 2x2 would be adequate, since there would be no load-bearing stress on the studs, no?