Studio Construction Concerns existing building shell

Hello all. First, let me pay my respects to everyone contributing to this forum. I have learned so much and also realize how much I have yet to learn. After many months of researching numerous subjects on this forum, I feel that I have a reasonable understanding of studio construction basics. Let me preface where I am at in my plans. I am in the design phase of my project. It is my intention to build a studio with two control rooms, one for me, and one for my partner. The studio will also have a live room and 3 isolation booths. The studio will have 2 bathrooms and a kitchen/lounge area. The type of music my partner and I work on ranges from rock and roll to jazz and pop to hip hop and urban music. Let me also preface that any construction will be permitted and to code. I have located what I believe to be a suitable building for my needs. I am currently in negotiations to secure the lease. It is located in North Hollywood, CA. The building is 2900 square feet, in an industrial park, built in 1960, and is of concrete block construction on top of a concrete slab. There is some existing infrastructure in this building already. It has 2 air conditioners on the roof. A 2 ton unit, and a 3 ½ ton unit. There are two existing bathrooms that are both ADA compliant. The entire ceiling throughout the building is insulated. One of my main concerns is an existing wall that divides the building into two partitions. It is of wood frame and drywall construction. I have no idea what is in between the drywall and studs. I assume that it has some insulation but we all know what happens when you assume. There is a tenant on the other side of this wall. He is an HVAC contractor. I am not sure what type of noise levels will be produced by his current business? I am also concerned about disturbing him. I have many questions regarding my studio design. First and foremost on my mind is what can/should I do about the dividing wall? Also, because this dividing wall will be one of the leafs incorporated into my design, I am concerned about the best way to maximize it’s effectiveness as far as isolation is concerned. My first thought would be to make sure that it is as air tight as possible, sealing every crack and seam that I can find. Next I would think it would be extremely important to add more mass to it via green glue and another layer of drywall. I am looking for any suggestion anyone can offer. Below is a sketchup model of the building as is it will be after some minor demolition. I have photos of the building right now but I hesitate to post them because they will likely be confusing when referencing the sketchup model. I also have several more questions and concerns regarding my design but I figure I will ask things one at a time. Thanks to all in advance for your help.

welcome! looks like a nice size space. one of the concerns you'll have with your neighbor is the flanking path along the exterior walls as well as the dividing wall. as far as noise levels, after you strip it out take some acoustic measurements to determine noise levels and evaluate the isolation - do some tap testing on the walls, floor and ceiling with metal and rubber hammers and if you can work with the neighbor to assess what kind of flanking you might have. assume (there's that word...) you have little flanking issues, then bulking up the dividing wall with additional layers of drywall would likely be a good idea. then assuming you have the rest of the shell sealed and isolation is generally acceptable so that it will work as a leaf, then a room-within-a-room approach should give you most of what you need.

Hi Glenn, Thanks for the reply and suggestions. I will do them and report back. I wonder if you would care to comment on this sketchup layout below. Please keep in mind not all of the details are finished but the main idea is to see if you agree that I have implemented some of the basic studio construction concepts (primarily MAM) correctly into this model. Perhaps it is hard to see some of the details but I would be happy to clarify if you have questions regarding what you are looking at. I know that from this photo it looks like there is no air gap between the control room walls and the existing shell walls of the building but it's just the angel of the photo. There is a minimum 8" air gap between the existing shell walls and the control room walls. Thanks so much, Erik

Just found out last night that I got approved for the building lease. I'm looking forward to getting this started.

I sat in the building all day with my SPL meter and my lap top taking measurements and making notes. Here is a picture of my amazing recliner in my newly leased building. Through out the day I heard/observed and measured the outside environmental noise from various locations within the building. I heard everything from planes flying overhead to trucks driving by on the street to jack hammers and metal grinding tools. The loudest things I heard and measured where the semi trucks that are driving by constantly. They ranged anywhere from 70 dB to 85 db depending on the type of truck. Most of the measurements were taking while sitting in the middle of the main warehouse area about 15’ feet from the loading door. The loading door is a simple metal rolling door and there is absolutely no seal around it. I can see sun light from around the edges and where the door meets the concrete floor. My neighbor on the east wall informed me that the we have a “pseudo” neighbor on the south wall who uses a jack hammer through out the day. He is in some type of concrete business? I say pseudo because he is in a separate building from ours, completely detached. His building is just in very close proximity to ours. There is about 10 inches separating our two buildings. I was able to take a measurement with my SPL meter while he was using the jack hammer and got a reading of 75db C weighted standing right at the block wall and adjacent dividing wall. I did not feel any vibrations through the concrete slab so it seemed that it was direct sound not impact sound that I was hearing and measuring. Hopefully somebody can help me make good use of all these measurements I have taken. I would like to propose some questions and see if I can’t talk my way through the answers. Let me preface that I am not a “math person” but I will make an attempt here. If the loudest noises I measured were 85-90 dB, and I want to establish an average noise level of 30 dB, then I would surmise that all of the construction that I will implement will need to attenuate 55-60 dB worth of environmental noise. Am I thinking correctly here? If this is true, then would I be correct in saying that a wall with an STC rating of 65 would be sufficient? I’m not sure if it is this simple or not but maybe someone can help me?!

with that level of sound coming from the jack hammer, you might put your ear to the ground (literally) and see if you can hear it through the floor. on the door - are you planning on removing it and framing up a proper wall to sit inside it? also, is your design completed or are you open for additional comments?

gullfo wrote:

with that level of sound coming from the jack hammer, you might put your ear to the ground (literally) and see if you can hear it through the floor.

While I did not actually put an ear to the ground, I did not "feel" any vibrations coming through the floor or block wall. It seemed to be direct sound. I will check it out again and see whats happening.

gullfo wrote:

on the door - are you planning on removing it and framing up a proper wall to sit inside it? also, is your design completed or are you open for additional comments?

As far as the loading door is concerned, we are planning to frame an entirely new wall with a proper door that will suffice for code and ADA requirements.