Sand for Mass?

Hi All, I have a large office building which I am contemplating converting a portion of to a recording studio. Not sure how much at the moment but wil upload plans as the idea begins to crystalize in my mind. One area I am considering is on the second floor. Perimeter walls are insulated builders block from early 1960's construction. Standard wood floorjoists and carpet make up the floor/ceiling between levels. There are also multiple windows which need to be addressed as well. Obviously sound isolation between the two floor levels is a consideration I am considering as a possible way to increase the mass with minimal expense to install a 4" layer of sand, then subfloor and laminate or other flooring material to finish. I am curious as to the use of sand as a sound treatment. This is quite an informative forum and I look forward to any inouts and advice along the way. More details in my next posts

Hello eurowolf, welcome. Adding sand as mass seems like a plan. It's heavy but not stiff. Good plan. But you need a good plan to actually have that build. need to check if floor can holt mass like that. Ask an engineer if yer not shure.

Sorry, I can't agree with Ro,,,,,,,, It's a bad plan........ even forgetting the fact that it will add 33+ pounds per square foot of load to te deck (odd are the deck will never carry that much weight). Aside from that - sand itself is not a stable material - just laying some plywood on top of it and the placing finished flooring on that will not stop it from shifting over time. So you'll wind up with some load on it - and then any small vibration will cause the sand to shift ever so slightly (at first) which will lower the floor there - and raise it elsewhere - and eventually you'll have to rip the entire thing out just to level the sand all over again. You said you "have" the building - and are obviously a business person - not some fluffy headed kid with visions of grandure........ so hire a professional acoustician in your area and pay him to design a solution that will fit your needs. Sincerely, Rod

Funny. I didn't, on purpose, write anything about the construction of such plans. It was, as I asume, just a global question. "will sand work or not". Tho I warned about the load. But Rod's right (ofcourse) in his arguments.

Ro wrote:

Funny. I didn't, on purpose, write anything about the construction of such plans. It was, as I asume, just a global question. "will sand work or not". Tho I warned about the load. But Rod's right (ofcourse) in his arguments.

RO, you definately warned about the need for an engineer to check for loading - I didn't mean to suggest that you didn't and I apologize for any confusion regarding that. You did (however) suggest that it sounded like a plan - in fact a "good plan" - and that it is not. It was that which I really spoke to. Sincerely, Rod

Whats wrong with the bottom/first floor eurowolf? It often works out better...not always, but the floor doesn't cave in :)

Okay, Rod. Thanx.