any benefit to quietglue/greenglue on studs?

[PAPAYAMON]

just wondering if anyone has applied quiet/greenglue to studs or joists before screwing drywall on?

it would be pretty cheap to do.

[Rod Gervais]

Originally Posted by PAPAYAMON

just wondering if anyone has applied quiet/greenglue to studs or joists before screwing drywall on?

it would be pretty cheap to do.

I doubt there is any real benefit - it is not an isolator - that is not how it works......

Rod

[andrebrito]

For vibrational purposes there are better products to do that rather than Green Glue

Green Glue only excels well when used in between gypsum sheets for airborne sound

[Ted White]

Well, I was there when this exact strategy was tested in Orfield Labs back in 2005. True to previous posts, it does nothing. As Rod said, that's not its intended purpose.

Green Glue damps vibration (airborne or impact) but does not decouple. Damping materials like this can be used between drywall, plywood cement board, etc.

Preferable to decouple via the framing method (staggered or double stud) or the use of resilient clips and drywall furring channel. I'd recommend avoiding resilient channel altogether.

[LegGodt]

Originally Posted by Ted White

I'd recommend avoiding resilient channel altogether.

Do you have data to support why you do not recommend resilient channel?

[DrFrankencopter]

I'm pretty sure that green glue works by shear force (effectively a relative sliding motion of the top layer past the bottom layer Shear stress - Wikipedia, the free encyclopedia ). When applied to the studs of a wall there isn't really any sheer since the drywall is screwed to the studs themselves preventing relative motion.

Cheers

Kris

[Ted White]

Noise Reduction Systems | Green Glue vs. Resilient Channel A good summary here.

The Steel Stud Manufacturer's Association tests and then specifies various structural parameters for steel building materials. C-channel, hat channel, steel studs, strapping, bridging, etc. No red structural steel, all commercial galvanized steel components. No spec for resilient channel, either as RC-1 or RC-2. So anyone who can bend steel can come up with their own resilient channel. Many different RC-1 profiles out there. Some 25 gauge, some 22. Some open weave, some slotted some solid and others are perforated. All would have different spring coefficients under the same load. Unfortunately, many manufacturers refer to the old USG channel lab test data when asked about the performance of their particular RC channel.

Of all the sound isolation products out there, RC-1 finds itself in court most frequently for one reason or another. A quick look at the NCAC member bios shows that a very high percentage of acoustical consultants list expert testimony in resilient channel litigation as one of their areas of expertise.

At some point a figure came out on the internet that the steel industry expects as much as 80% of all resilient channel installations are short-circuited. While this is an often-cited statistic, I have yet to find the source of the data.

[Ted White]

Kris, you're right on. Constrained Layer Damping systems rely on the application of shear force to the damping layer to convert the vibration to heat. This requires a large surface area to perform meaningfully, which is why it works great between drywall over the entire partition. The face of the stud or joist does not provide enough surface area.

As you pointed out, and prospective decoupling strategy at the stud or joist face needs to be free to oscillate, and the screws remove the ability to meaningfully compress. As well they provide conduction. This is the problem with sound boards. Using sound board on a stud wall can provide a degree of decoupling untill you shoot the stud face full of drywall screws.

[Rod Gervais]

Originally Posted by LegGodt

Do you have data to support why you do not recommend resilient channel?

The biggest issue with RC-1 & 2 is (from my perspective) that the installer can screw up the system quite easily - and they usually do.

Either they install the channel upside down - or they (inadvertently) screw through the channel directly into the studs/joist when they install the drywall......

Inspections therefor get pretty extensive - especially with multiple layers of drywall. You have to inspect prior to drywall - make sure they have the various joist/studs marked at each end of the assembly (so you can verify that the screws are not in structure) and do this for each layer prior to covering anything up.

It is a real PITA - and the bigger the project the more of a PITA it becomes (I did this on the outside walls of a 21 story Hotel once - trust me when I say it's a royal PITA)

That having been said - I have specified RC-1 on projects where I have a physical presence - and when properly installed (under my watchful eye) I have never had a system fail due to the product itself.

The various RISC systems are pretty much idiot proof........

Rod