neoprene advice

Hey all, I've been away for a while and been a bit busy but now getting back to building my studio again. I've been researching the neoprene vs auralex U blocks for some time and based on the input I received from here it appears I would have a better isolation in my control room if I use neoprene. I found what I believe will work but have seen reference to many different types of neoprene as in open loop and such and require some advice as to if the neoprene I am looking at is the correct type. http://www.rubbercal.com/Neoprene.html I'm look at the 1/2" 36"x25' roll which is rated at 55-65 durometer. Thanks :) James

That's the correct density, but I'm not sure where you got the idea that neoprene is better for isolation than EPDM, which is what Auralex U-boats are made of; in fact, EPDM tends to have quite a bit longer useful life than neoprene, in some cases about double. I'm not sure what you intend to do with it though; have you read all the caveats about INCORRECTLY floated floors, or done any MSM calculations to see what benefit (if any) this will give? Just curious... Steve

Hey, Thanks for the reply :) My intent was that I am trying to leave as much of the 10ft floor to ceiling as possible so i intend on laying the 2x4s sideways. I had looked at the UBoats and was going to go that route but it seems that neoprene is a better product for inbetween the floor, 2x4s and was thinking the flooring itself once I get the weight calculations...I did read many of the threads that compressed neoprene might as well be no neoprene and that getting the top weight calculations correct is required in order for the neoprene to work correctly so once I get the flooring setup I need to do compression tests and adjustments for the equipment. I'm a complete noob to this and as this is a 1st attempt on this room but I have been taking my time for the past 3 years and wanting to get this going again...those 60 sheets of drywall are still sitting in my front living room :( I still want it to sound great and be isolated for the 3am sessions but I definately don't want to be cheap about it and not do the research on different solutions that might work better...The ceiling,existing house HVAC and copper pipes are going to be my biggest issues for noise so I'm reading all the experience and solutions people have used on here. James

knightfly wrote:

. . . in fact, EPDM tends to have quite a bit longer useful life than neoprene, in some cases about double.

Steve, Is this claim documented anywhere though, other than the U-boat manufacturer saying that is what someone said to them once? :roll: We already know that they didn't put U-boats through any rigorous (or any?) testing... :roll: James, it does appear that you know the perils of an incorrectly engineered floating floor -- overloading especially. However, there is also the risk of underloading. There is also the risk of too small a gap between floated floor and its subfloor -- and floating a floor using 2x4s laid flat gives you just over 1 1/2" of an air gap between floors, which is woefully insufficient for any M-A-M benefit. There's also the issue of what kind of floor you intend to float. It has to be massive in order to be effective... And I'm betting that with your minimal vertical clearance, you can't afford the space to have a thick enoujgh floor to make it worthwhile. Floating a floor may not be an option for you. Besides, you haven't said what type of surface you intend to put this on... Basement slab? Slab on grade? Raised wooden subfloor? Upstairs over a garage? There are significant ramifications to each of these scenarios, some of which make it practically impossible to float a floor safely. I realize your question was targeted and specific, but the question needs to be put into context. That's why following all of the critical bold items points documented in the "Before You Post" announcement are so important. :) --Keith :mrgreen:

Thanks sharward, any and all advice is appreciated. Its going on rough concrete that is isolated from the walls with a fiberboard. I didnt think about the spacing and as such have purchased the auralex since it would work with me using them the normal way for the airspace. I need to get back to reading this forum for the isolation and such for this control room as there is soooo much material to reference and figure out what would work best for the room without losing too much space. James

How about if someone were just wanting to 'isolate' or maybe rather 'gasket' the inner- and outer-leaf baseplates? Both my baseplates will be resting on the concrete floor, and will likely be made of PT 2x4's.... Wondering if it would be advisable to use some sort of plastic/rubber under them? ... if not for the sake of just keeping them not directly on the concrete (wood to concrete)... No real liquid water problems, but potentially seapage if it's covered up as such. Plus, I'm assuming there will surely be irregularites in the wood that might make creating a good 'seal' to the floor difficult... But I've been seeing in some previous posts that it's 'not recommended' to use anything at all beneath the baseplates... so I guess that's the answer? Any ideas greatly appreciated here.... thanx, K

There is a product called Sill Seal that does a good job of accounting for the irregularities of a slab and the soleplate. I plan to use them when I do my framing. However, you cannot legally and safely "float"wall frames. They must be firmly attached to the slab. Even if you could, Sill Seal wouldn't be the product for that. The firm connections into the slab that will hold your wall frames in place will negate any attempts to decouple the frames from the slab. --Keith :mrgreen:

Even pressure treated wood should have what's called a "thermal break" between it and concrete - I've used 2 layers of 30# roofing felt in several places and it works well, or the sill seal product which is intended just for this. The actual seal in a sound wall does NOT depend on a tight seal under the frame though; there are a couple of threads in the REFERENCE section on drywall, caulking, backer rod, etc, which explain this... Steve

That's what I had thought about the PT, that it should have 'something' under it.... just didn't know what was best... I'm not really looking to decouple the floor from the wall at all, not to float per se,,, that is I just thought of some sort of gasketing would be good... I realize that there will be acoustic caulking at the bottoms of the sheetrock layers (where they meet the floor), but figured 'redundancy' of sealing was not a bad idea... thanx, K

knightfly wrote:

Even pressure treated wood should have what's called a "thermal break" between it and concrete - I've used 2 layers of 30# roofing felt in several places and it works well, or the sill seal product which is intended just for this. The actual seal in a sound wall does NOT depend on a tight seal under the frame though; there are a couple of threads in the REFERENCE section on drywall, caulking, backer rod, etc, which explain this... Steve