help needed isolantion concrete slab

hi everyone! i´m new at this forum and it seems to be great! i´m from portugal. i need some help!i aprecciate any input i´m building a new studio.it has (15 meters)49 feet long and (6 metres)19 feet wide and (3 meters)9 feet high. it can be well divided for a nice control room a nice live room. the thing is i cant decide how to do the srtucture. it´s on the ground level.so it has dirt and gravel for now and i want to do an isolated concrete slab. i´ll do expansion joints to divide the rooms,but should i use some material under the concrete.how thick must the slab be? how can eliminate vibrations the best possible way~? thanks for your help regards vidal

What you can do, vs what you can afford to do are two different things... Have you got a budget? The floor is really dependent on your walls and ceiling... which again, depend on how deep your pockets are... Have you got a budget? And at what level is the venture going to operate? A pro studio? project studio? home space to mess around with? Unfortunately, it come back to how much money you got? Oh... and have you got a budget?

There should be something like "I agree that I have read the forum and it's stickies" button for newbies ... :mrgreen:

thanks for the reply! i do have a budget, but the only thing i rule out is an elevated concrete slab. i want to do a pro studio, even if it takes some time to be perfect, but for now i want the best structure possible.i want to eliminate vibrations and all the sounds that come from the street and neibhougrs. i have pillars that are connecting the floors,so i have isolate that.i ´m going to make walls that not touch the new and old structure with concrete blocks filled with sand.those blocks will grow from the new concrete floor that doesn´t touch the walls .that new slab is right on the sand and dirt. that´s my ideia for now. really aprecciate any help! thank you best regards vidal

<sigh> Not tryin' to beat ya' down Vidal, but you GOTTA supply more info than this if you want serious help. It seems that you don't appreciate just how technical this really is. You build correctly, and you can have a great facility... You build wrong.... people are DEAD. This is why Ro made the comment that it would be nice if there was some way to force people to read the stickies at the top of the forum. Just so there's no mistaking that you won't read it.... Welcome to the Studio Construction forum! I've been hoping to find time to do this for some time now, and Sharward, one of our newer members, did an eloquent job of saving me the trouble - here, with possible MINOR changes, is what we ask of you BEFORE POSTING - Edit - So few people have been supplying the information asked for in this document that I've decided not to answer ANYONE who doesn't comply. This is not arrogance on my part, it's based on TIME - it takes me several times as long to help someone who doesn't even bother to READ the links mentioned here, much less study them. I no longer HAVE that much time (never did) so I have no choice but to only help those who pay attention. This means - No location, no answer. No attempt at providing room details, no answer. (If you try, and I need more, I'll ask.) The effort you put into your question(s), I will put into my answers. I'm sorry it has come to this, but it has. Bottom line is this - if you are willing to put in the effort, so am I. If you are in the process of planning the construction of a studio, this forum contains a wealth of information that will help you, along with many knowledgeable members who can offer you advice with your project. Before you post any questions, please take a few moments to follow these steps - keep in mind that any print in bold type means we need you to pay attention - I don't just randomly bold things unless I consider them important. Review the REFERENCE area - http://www.johnlsayers.com/phpBB2/viewtopic.php?t=2125 This is the closest thing we have to Frequenty Asked Questions on this resource at the moment. Many common questions are covered there, and it is required reading in terms of our being able to help you with your project. Use the search feature to look for threads that may contain the answer to your question. There is a wide variety of projects represented in this forum -- everything from relatively low-budget residential rehearsal rooms to full-scale, professional recording studios. If your searches return too many results, try multiple terms with "Search for all terms" enabled. If those efforts do not lead you to the answers you need, you are welcome to post your questions on the forum. If you do so: Edit your profile to include your location. This is very important, because this is a worldwide resource, and as such, material costs and availability vary widely. For example, masonry is cheaper than gypsum in some parts of the globe, whereas it's the exact opposite in other regions. We're not asking for your address or credit card number, just a country will do. Nothing says "I didn't bother to read or follow these instructions" like leaving your profile location blank! :x Start your post with an overview of your goals and where you are in the process... Research? Planning? Construction already underway? Finished, and wanna know why it doesn't work? :cry: HOW LOUD are you, and how picky/loud are your neighbors? How close? This is subjective, so you will need to buy something like the Radio Shack Sound Level Meter Trust me, if you're recording/mixing music you should be using this ALWAYS, so it's not a waste of money. For music at typical mix levels, you want to use "C" weighting, slow. The human ear has no way of "measuring" ABSOLUTE sound levels; it just adapts to what's there, and calls that "normal" - so if you keep raising the volume, pretty soon you're mixing at 110 dB, ruining your hearing and neighbor "atta-boy" points, etc - the SPL meter helps you keep levels constant and safe. For all other tests, the authorities virtually ALWAYS use A weighting, and (I think) slow response. So for compliance, use "A" weighting measurements. Include as much detail as possible about the existing construction. Having details about anatomy of your existing floor, walls, and ceiling is critical. In your searches of the forum, you'll likely find examples of the kinds of details that are needed, and you'll see that the quality and timeliness of the advice given are affected by the level of detail provided. New, 7/24/06 - By "detail", I mean enough detail so I might be able to go buy materials and actually BUILD a nearly identical version of your construction; things like type of material, size of framing if it's visible, style of construction - without this level of detail we can't recommend much of anything. NEW - Please don't tell us you want to float your floor if you are building on an upper level - this is almost always impractical, and ALWAYS will require a LOCAL ENGINEER to verify that it will be safe. Remember that acoustics is THREE DIMENSIONAL, not two - when you give dimensions, we need Length, Width, Height, plus any NON-parallel features of the room. Include drawings of what you're describing if at all possible. They do not need to be professional or perfectly to scale, but they do need to account for the necessary details. Cropping your drawing will allow you to make the important parts larger and more legible without increasing the overall size. See next... Please resize as necessary to keep graphics BETWEEN 700 and 750 pixels wide - otherwise it's either too small for details or it forces people to scroll sideways to read every line of text. :x If you link to pix OFF this site, please make sure THOSE pix aren't oversized either - it causes the SAME PROBLEM. New, 7-5-06 - From now on, please post ALL pix directly on this site instead of linking to them; I've had too many cases of lost pix when referring new members to threads that would have helped them. Posting the pix HERE would ensure that others get the help YOU got; thanks... Posting L-O-N-G links - long links will also cause people to scroll sideways to read every line of text - here is the trick to avoid that, please use it for long links - [url=LINK]TextYouActuallySee[/url] I keep a word file on my desktop with the above line, then cut and paste everything ahead of LINK into my post, then the long LINK, then close the brackets as shown, then type what shows on screen (TextYouActuallySee), then close with the bracketed [URL] - for me it's just easier to use cut/paste. However you do it, please do it. Group your actual questions last, and put each question in its own paragraph. This makes it easier to respond to each of your questions. ...and finally... Please be patient. Questions are answered in the order received (oldest first), so "bumping" your post may actually delay a reply. It may take up to a week or longer for a response (this will rarely be the case), but you won't be forgotten. If you care to ask an additional question or provide more information before you receive a response, we recommend editing your post instead of bumping, as that will allow you to retain your position in the queue. Again, welcome to the forum, and good luck with your project! (And thank you, Kieth, for a really helpful addition to the site) Steve One more point you need to include - Budget - without this we have no idea if we are wasting our breath suggesting things - answers like "small", "REALLY tight", "reasonable", etc, have no meaning whatever. Comments like "under $500", "prefer to keep it under $1000 but can go more if necessary", "$300-$500 MAXIMUM", will give us a clue for realistic suggestions.