[apa]

Has anyone ever used this stuff? It's meant to be sandwiched between
layers of drywall to increase transmission loss.

[Mark]

http://johnlsayers.com/phpBB2/viewto...ght=green+glue

[Arny Krueger]

"apa" wrote in message
ups.com

Has anyone ever used this stuff? It's meant to be
sandwiched between layers of drywall to increase
transmission loss.

Never heard of it. Read quite a bit about it. Interesting stuff for making
walls and the like. Now I've got the same question you posted! Is it as
good in real life as it looks on paper?

[Arny Krueger]

"Mark" wrote in message
news:kwqph.18066$Pe7.12312@trnddc04

http://johnlsayers.com/phpBB2/viewto...ght=green+glue

Which points to

http://forum.studiotips.com/viewtopic.php?t=2015

Which seems to support the use of Green glue, always for ceilings and maybe
for walls.

and

http://forum.studiotips.com/viewtopic.php?t=2027

which has a lot more details about building ceilings

[Gil]

Yes, I used it on a recent soundproofing project. What it does, when used
properly (sandwiched between two layers), is dramatically cut down the
resonance of the layers of whatever. This'll help the transmission loss.

I haven't yet done the "after" testing for my project, but my gut feeling
is that it helped a lot.

[[email protected]]

I just purchased about $2500 worth of Green Glue in an attempt to
maximize isolation in a studio I'm building. It'll be going between
layers of 5/8 plywood and 5/8 drywall on eight interior walls and a
ceiling as well as a decoupled secondary interior wall that encloses
the two rooms. If you follow up with me in two weeks or so, I'll be
glad to let you know how it went - working with the product, and my
assessment of the results.

Cheers,
Steve





Gil wrote:
Yes, I used it on a recent soundproofing project. What it does, when used
properly (sandwiched between two layers), is dramatically cut down the
resonance of the layers of whatever. This'll help the transmission loss.

I haven't yet done the "after" testing for my project, but my gut feeling
is that it helped a lot.

[[email protected]]

apa wrote:
Has anyone ever used this stuff? It's meant to be sandwiched between
layers of drywall to increase transmission loss.

OK. I am an occasional lurker here, and for the record have not used
"green glue" or any other exotic material, but I have done a fair
amount of sound-control wall designs with specific reference to
surgical suites, high-end multi-family residential, isolation of
emergency generator systems in hospital and educational settings and so
forth. So I will write only to general principles of sound control.
They are in no particular order:

Mass - greater mass will help reduce low frequency transmission.
Lead-lined GWB (gypsum wall-board) with proper attention to
penetrations is about the best sound-deadening material available. Not
cheap but readily available and nothing special to handle or install.
Isolation - Isolation of the several elements of a wall will help
reduce mid and high-frequency transmission. RC-1 resilient channel 24"
OC is an excellent isolation material. If sound-deadening adhesives are
used with it, it is even better. Staggered studs isolating one side of
the wall from the other is also excellent. Setting the studs at 20" OC
and then setting RC-1 horizontally at 24" OC is even better. Setting an
internal layer of GWB that becomes the HF barrier is even better. But
the wall gets thick in a hurry.
Stud/support spacing - Support spacing will help reduce sound
transmission by resonance. 16" OC (for example) used with GWB will
resonate at about the same frequency as a 5-liter diesel engine on
heavy-load acceleration. Really.
Flanking - Sound will penetrate the smallest of openings, such as
around electrical boxes, duct penetrations, pipe penetrations, edges of
the individual boards and so forth. And a little bit of caulk has NO
effect on flanking. Pieces of GWB and/or lead foil are required to
address this issue correctly.
Fasteners - Fastener spacing _AND_ adhesives make a difference. These
must be used together with a flexible adhesive and fewer rather than
more fasteners. The two taken together will increase isolation of the
elements.
Floor, ceiling and wall construction - If one wishes to isolate a
specific location in a given area, unless attention is paid both to the
floor and the ceiling, sound will flank via the structure no matter how
the walls are constructed. So the sound attenuation materials must
"turn the corner" so to speak. Typically this means a suspended
hard-surface ceiling and an isolated floor. Equipment mounted later
should be on resilient pads designed *specifically* against the weight
of the equipment. One size does not fit all.

And when one is done with all of the above, then one must address room
acoustics.

Comes to it, any one bit of material is only one bit of the puzzle. All
must work *together*, or none will work at all.

So, unless careful attention is paid to all of the elements noted
above, even the very best "Myrycal Shyte" will do nothing at all,
whereas standard off-the-shelf materials installed with care and
attention and understanding of the various necessities will do quite
nicely, thank you.

Peter Wieck
Wyncote, PA