Hello Hummarstra. Let me clarify something. First off, my disclaimer. I am NOT an expert at this stuff by any means. There are members here who are far more enlightened than I, so anything I tell you is my OPINION, and subject to others clarification, guffas, razzberrys and outright
But I think my opinions are in the ballpark so to speak. The thing is, it is very difficult for people here to predict exactly what the different aspects of your goals are. Type of music, db profile of what your are recording, environmental noise, containment aspirations, budget, skills, existing construction....all have a bearing on the final choices for materials and techniques used in your project.
However, my main job around here
is to extract enough information from people, to bring these aspects to the forefront, so myself and others have a better overview of your the problems at hand, in order to suggest relevant solutions. Otherwise, we are spitting in the wind. So before getting into the actual suggestions, lets look at the information you have provided so far.
This proposed project is going to be in the corner of a basement.
All of the walls of the basement are CONCRETE, and are FULLY below
grade.
Your plan is to build a room in one corner of the basement, utilizing 2
of the concrete walls, and building two NEW partitions(leave out the double wall scenario for now.)
The floor of the basement is wood, with 2x6 joists, with a small crawl
space below it and chipboard sheithing.(OSB or particle board
underlayment?)
Ok, you are completely correct. We need MUCHO more information to begin suggesting things.
Here is what we would LIKE to know. Starting from the ground up.
1. Are these concrete walls simply a foundation footing for the structure above?
2. When you say crawl space, how deep is it from the ground below to the bottom of the joists, and is there any insulation in the joist cavities?
3. I assume you have actually looked into the crawl space. Have you seen any evidence of water collecting under there, or through the walls?
4. Can you see any RIM joists at the walls that the floor joists die into?
5. If applicable, are these RIM joists and floor joists setting on a wood plate, that in turn is resting on a thickened portion of the concrete walls? In other words, is the foundation or footing thicker under the floor framing than the walls are?
If not, exactly what is supporting this floor? Are there any concrete
piers under the span or is there any beams supporting the joists at the center of the span?
6. What is the spacing of the joists center to center?
7. What are the dimensions of this complete floor? Width and length to the walls. Height of the room, from existing floor sheathing, to the underside of the joists above(if exposed, if not, to the finish ceiling.)
On to the walls.....
8. Can you determine the thickness of the concrete walls?
9. How far above grade do these walls extend before the framing of the first floor begins?
10. Are these walls solid concrete, or concrete block with a plaster coat?
On to the existing ceiling and general information....
11. What room is above the area that you plan on as a room?
12. Is the existing ceiling in the basement already finished, or is it exposed framing?
13. If finished, what is it?
14. If exposed framing, how deep are the joists, and what is the subflooring and finish flooring above?
15. Are there any things adjacent, or within the space you are enclosing, such as HVAC, pipes, stairs, radiators, fireplaces, electrical supply panels
etc?
16. Are there any HVAC ducts in the joist cavities above this proposed space?
17. What are you planning as far as HVAC or ventilation in this space?
General..
18. What are your general isolation goals? In other words, what are you trying to isolate, airborne sound in the studio from transmitting to the upstairs and the adjacent room in the basement? How about structural transmitted noise generated above, like footsteps etc. Any neighbors within 20 feet? How about environmental noise like aircraft, street traffic, industrial noise such as manufacturing or transportation vehicles(trains, trucks, etc?)
What kind of music are you dealing with, and exactly what are you going to be doing? Recording live voices, instruments, direct to board, mixing, band practice etc? Any live drums? Bass?
Where are you located?
Are you planning on getting permits?
Any electrical work?
Well, that's enough for now.
This will give us an idea of what you are dealing with. Budget, skills etc are next. Maybe give us a hint too. Like I said, it all has a bearing.
fitZ
, IF your isolation needs are not that great, as in "flute solos" vs ROCK DRUMS...maybe some alternatives would be good to know, such as alternate stud construction vs double walls, and resiliant channel on furring strips on the concrete wall, with rigid fiberglass between the furring strips, and batt type insulation between the alternate studs. Yell if you want more information, or simply do a search for these terms here.
. Because of soil conditions there, floors in basements cannot be used to support additional loads in basements. NOW, I don't want to imply that this is YOUR condition also. ONLY MAYBE. But what IS important, is for YOU to check with BID(Building inspection department) and find out what the deal is with your location and any reletive codes that place restrictions on this type of "remodeling". Studio walls are extremely heavy, so you REALLY need to know what you are dealing with in reality here.