Home studio in my basement, construction questions

I will be finishing my basement within the next week or so. I will be using construction techniques with the intent of increasing isolation from the rest of my house. The house is a semi (I know, I know, don't worry). Neighbours are not an issue. I am trying to isolate from the upstairs living areas and bedrooms. I don't need to be able to play drums while people are sleeping right above me, but I'd like to be able to record drums, guitars, vocals, etc. without having to kick everyone out of my house to avoid footsteps on my tracks. I have at my disposal the upper level of the basement. The 3 exterior walls are bare concrete, the floor above is hardwood so I have basically no sub floor. The floor is concrete slab. The layout is not up to me really. My mom has agreed to finish a living space, not a full fledged studio. So the layout has to be thought out with future owners of the house in mind. Also, I may not be living at home next year or beyond, so I would feel bad going all out on this only to leave my mom with an unsellable basement with a ridiculous layout that really only appeals to a home studio owner. SO. Here's the steps I'm planning on taking, followed by my questions. CEILING: 1. Beef up sub floor between joists with 2 layers of drywall (or one layer drywall, one MDF, not positive yet, chime in if you wish), with green glue between layers, all sealed of course with acoustic caulk. I can't screw up into the subfloor as its way too thin, so I will be using 2x2 screwed into the joists to hold up the drywall as snug as I can get it. 2. Fluffy pink stuff below that. Do I need vapour barrier here? I don't think I do... 3. Another layer (possibly two) of sheetrock with green glue on the bottom of the joists. Have considered RC here...don't really want to though. Too many variables... WALLS I'm basically only building two walls, one spanning the width of the space, and one separating the "booth" from the area with the two stairwells. For both, I want to do double wall steel stud walls, with two layers of sheetrock with green glue on the inside (studio side) and one or two layers on the other side. The walls will be surrounded by a 1/4 inch gap between ceiling, floor, and corners, sealed with backer rod and acoustic caulk as per my research. The two doorways will be double doors with the best seal I can build. So far so good I hope? Questions: 1. Should the top plate of my walls be attached to the ceiling joists? If not, what are my alternatives that would improve the isolation performance of the walls? 2. The 3 exterior walls are currently painted concrete. I'm fine with how they look. I don't want to frame and drywall them simply for appearance, I rather leave them as is and spend more money and effort on the one wall and making that very sound proof to isolate the studio from the lower level and upper level stairwells. If my ceiling goes right to the huge piece of wood around the perimeter to which the joists are attached (Soffit? I'm not sure what this is called, sorry) and is sealed there properly, will that be just as effective as butting the ceiling up to a sheetrock wall? 3. Layout aside, any criticisms or corrections of my plans would be greatly appreciated and respectfully considered. Here is a sloppy, but accurately measured diagram for better understanding...The 3 outside walls in gray are concrete. The orange wall at the top is drywall from the upstairs stairwell to the right wall, and from the left of that stiarwell all the way to the left concrete wall there is nothing. It is open to the lower level of the basement, including the washer, dryer, fridge, furnace, water heater, and a bunch of other things that enjoy ruining my recordings. I will try and get some decent pictures with some sunlight in here tomorrow. Thank you so much in advance. I've learned a shitload from these boards, and I can't wait to apply it to my own space! -Adam Marshall

Hi there, Take a good hard search on flanking and rethink your ceiling and bare walls. Also, what is directly below you? Steve

I have an idea of what flanking is but those walls im talking about are like a foot of concrete. If the ceiling is sealed to the walls, shouldn't that be okay? Also, the floor is the foundation of the house, solid bare cement. Adam

As far as resale value, I would flip the bathroom space and the booth/closet space. I would rather have a window in a bathroom than a closet!

you planning to add 4 layers of drywall to your existing joists. I would suggest a engineer to check out your structure to ensure its safe to do so. I think it would be very unwise to attach any of your studio walls or ceiling to the existing ceiling joists. I would suggest decoupling your inner leaf from the outer leaf. You could do the RC (some folks here could help you with the variables) Or hang new ceiling joists supported on framing. ( but then you'd have to frame where you want to leave it concrete wall.) but this framing might be good for acoustic treatment if you don't want to drywall it. Or special hangers attached to existing joists. If your going to the large exspence of green glue between all layers it'd be foolish not to decouple properly. good luck with your build, -Pete

marshall409 wrote:

I have at my disposal the upper level of the basement. The 3 exterior walls are bare concrete, the floor above is hardwood so I have basically no sub floor. The floor is concrete slab. You can seal the ceiling to the concrete, as you say. Putting a big "lid" on the room reduces the need for heavy sound isolation on the walls. SO. Here's the steps I'm planning on taking, followed by my questions. CEILING: 1. Beef up sub floor between joists with 2 layers of drywall (or one layer drywall, one MDF, not positive yet, chime in if you wish), with green glue between layers, all sealed of course with acoustic caulk. I can't screw up into the subfloor as its way too thin, so I will be using 2x2 screwed into the joists to hold up the drywall as snug as I can get it. This would be more effective with two layers on mass + damping rather than one layer. Constrained Layer Damping is more effective in layers, even if the same fixed amount of damping material is used and simply split into two layers. 2. Fluffy pink stuff below that. Do I need vapour barrier here? I don't think I do... Don't need it, but there's no harm and the paper can be stapled. The paper isn't significant enough in mass to define a leaf, so no risk of a triple leaf. 3. Another layer (possibly two) of sheetrock with green glue on the bottom of the joists. Have considered RC here...don't really want to though. Too many variables... As mentioned it would be a shame not to use double drywall on a decoupled spring system. Clips + channel, for example. The added mass of double rock here will really drop the resonance point. Damping will reduce the resonance. WALLS I'm basically only building two walls, one spanning the width of the space, and one separating the "booth" from the area with the two stairwells. For both, I want to do double wall steel stud walls, with two layers of sheetrock with green glue on the inside (studio side) and one or two layers on the other side. The walls will be surrounded by a 1/4 inch gap between ceiling, floor, and corners, sealed with backer rod and acoustic caulk as per my research. The two doorways will be double doors with the best seal I can build. So far so good I hope? So far, so good . Questions: 1. Should the top plate of my walls be attached to the ceiling joists? If not, what are my alternatives that would improve the isolation performance of the walls? Consider connecting the top plate of the inner wall with something like the PAC DC-04 clip. 2. The 3 exterior walls are currently painted concrete. I'm fine with how they look. I don't want to frame and drywall them simply for appearance, I rather leave them as is and spend more money and effort on the one wall and making that very sound proof to isolate the studio from the lower level and upper level stairwells. If my ceiling goes right to the huge piece of wood around the perimeter to which the joists are attached (Soffit? I'm not sure what this is called, sorry) and is sealed there properly, will that be just as effective as butting the ceiling up to a sheetrock wall? Better if you can run the ceiling to the slab, rather than that sill plate. 3. Layout aside, any criticisms or corrections of my plans would be greatly appreciated and respectfully considered. Here is a sloppy, but accurately measured diagram for better understanding...The 3 outside walls in gray are concrete. The orange wall at the top is drywall from the upstairs stairwell to the right wall, and from the left of that stiarwell all the way to the left concrete wall there is nothing. It is open to the lower level of the basement, including the washer, dryer, fridge, furnace, water heater, and a bunch of other things that enjoy ruining my recordings. I will try and get some decent pictures with some sunlight in here tomorrow. Thank you so much in advance. I've learned a shitload from these boards, and I can't wait to apply it to my own space! -Adam Marshall

Take care framing around that support beam and column. Good that you're not near the stairwell.

"3. Layout aside, any criticisms or corrections of my plans would be greatly appreciated and respectfully considered. " You have to consider that there are Professionals here that are far advanced in experience then you are. So unless you have credentials, then you are going to get hit on. For me, most of what you are saying is basic construction technique, read from a book as it were. To get more accurate...your detail is lacking and it is difficult to get a handle on what ceiling and what wall you are referring to in what area. One thing I will say: You have to spend time with your "experts" to know if they are going to lead you down the road to isolation heaven or the hell that construction can be.