Soundman2020 - Studio Design Forum

First and foremost,
Hanging pictures of kittens was the original reason why sound rooms were built. (Sorry, I got a kick out of the verify questions.)

Ok.. Hello sound a-tunement aficionados. This place is sooooo informative! I'm so glad I found this site while stumbling around online searching for answers for my project. I am in the process of building a home live music / golf simulator / bar rec room in my basement. I am, in no way, in the same league as any of the people who post here about technical info, but I have a firm grasp of the concepts in sound isolation. I've been involved in music and carpentry for most of my life and I'm looking for a little, information, confirmation, salutation and less aggravation.

My goal is to create a space to live jam/record music while reducing the db by at least 60. I must install a bathroom and a 3' high set of stairs, which is depicted in my layout. There is an electrical panel that I plan on making an access door for in the bathroom (another area I have questions about in the ceiling area). The other amenities are not relevant for sound isolation except for maybe one parameter that I will address later in the post.

I apologize up front if my descriptions and or sequence of content gets a little scatter brained. Alright onto the info. The basement space is 25' x 32' x 10' - Concrete slab floor - 8"cement block walls - 2"x12" ceiling joists. There is one door attaching the front of the house basement to the back of the house basement 3' up, and one door to the exterior of the back basement. The block walls are underground 6' on the sides and fully exposed in the back. The block wall next to the front of the house has a 1' space between itself and the foundation for the front of the house. The living space above the proposed jam room is my living area. Reducing db for the front portion of the house that I rent out is paramount.




I plan on having fully decoupled framing on all walls and ceilings. My original thought was to set 1 5/8" steel stud 24" on center 3" away from the block wall and have it closed cell spray foamed for a vapor barrier. Then come out another 1" and start the 2x4 wood framing for finish walls with r-15. I'm not sure about the spray foam anymore after reading through some posts here. The ceiling in the main area would be 2x8 doubled at 2' centers with dbl SR and GG w/ r-19 insulation. Leaving me about 9'2" ceiling height. For the ceiling in the sim room portion, I was planning to use 2x4 on 16" centers (possibly doubling every other joist) with a strong back to help support the thinner timber, leaving me 9'6" (Need the swing room clearance). To try and seal off the ceiling bays from reaching the front portion of the house, I was thinking to maybe set bridging in the bays with triple sheet rock sealing each layer. Every new door opening will be a solid core double door system with seals and added layers if needed. The plan for the floor is glued down vinyl planking 12mm thick. For lighting and outlets I plan on running one main conduit along the finished ceiling from the main panel branching off where needed to wall/ceiling mount devices and then making decorative soffits and wall treatments to mask so the room is penetrated only once for all electrical. Mini split for HVAC TBD for placement. Fresh air intake needs my attention.



I am currently in the process of taking out the existing r-30 insulation in the ceiling and attaching two layers of 5/8 sheet rock with green glue in between each layer to the sub floor in each bay, sealing the edges of each layer and all corners, joints and hangers of framing with big stretch. Then putting the r-30 back. The bridging is under the sheet rock.



Q 1. Should I use a wider steel stud and allow room for pink insulation in front of the spray foam on the vapor barrier, or is there a thinner alternative? I know block seal paint exists but I would like some sort of R value off of the block.

2. Should the top of the vapor barrier framing be attached to the existing ceiling or to the block wall? The structure sits on the block so does it make a difference?

3. Should I use some sort of rubber/ truck mud flap/ piece of tire to isolate the lolly column mounting areas? It's not structural, I put it in to reduce deflection of the beam. See proposed rendering.

4. Is it a good idea to run bridging and layers of sheet rock across the front block wall in the ceiling bays to isolate the front of the house, or will that create a problem? (The wall behind the temp golf simulator in pic 1) There is about 20" or so to the framing ledger on the front portion of the house.

5. I am concerned with the ceiling area bay above the electrical panel. Should I try and quarantine it somehow one bay over? Not really sure about this one. see pic below



Realizing there are many more things to cover, this should be a decent starting point. This project is tasked by myself, so it will take some time to get completed. All replies are greatly anticipated and appreciated. Thanx in advance, Greg

using the foam on the block with the 1-58 to create the insulation / vapor barrier seems reasonable. then just treat that as your exterior bounday when consider your next layer of framing. then on the front portion of the basement have your double wall. on the bath room side i'd just extend the wall across to match the "sim room" and only a single double door into that space - you "lose" some space for the sake of simplification and ease of use for the rest of the basement + more isolation from a single opening.

Thanks for the reply Glenn,
I was under the impression that the foam would be too stiff of a surface. Shouldn't I try and attenuate in front of the foam with at least 1" fiberglass panels or something?

GKurtz wrote:Source of the post My goal is to create a space to live jam/record music while reducing the db by at least 60.

With the caveat that I have no personal experience of intentionally achieving as high a level of reduction, my understanding from the builds of others is that 60dB of full audible spectrum reduction is quite challenging to achieve, particularly when retrofitting a domestic property constructed on a single slab.

If you have not done so already it might be worth looking further into this and adjusting expectations or build techniques accordingly.

Cheers,
Jennifer

no, put the foam on the block/concrete. it's just part of the exterior boundary.

as Jennifer noted: residential construction (with few exceptions) do not get a full 60db transmission loss esp below 125hz. there are many reasons for this including sound levels at those frequencies, framing and window/door material limits, and structural transfer.
in the case of connected structure (meaning your concrete floor for example) pretty much the maximum is around 55db because even if the walls ,doors, and windows are doing a great job, the concrete (which even earth damped) is a great conduction medium of sound energy (10x the speed of air typically). and then once it's in the structure, and resonances from other structure effectively amplify those frequencies. ducts, pipes, frames, floors, appliances, furniture, things in the kitchen cabinets, etc...

so in terms of expectations: let's say your playing is 115db with drums, bass, guitars, keyboards, people screaming over top of it to be heard, etc. and you get 45db of decent across-the-board isolation, how loud is 70db? with most of that LF. and based on your hearing - what is the perceived level? so keeping things from resonating and rattling will become the next exercise.

using isolation platforms on drums and instruments, decoupling speakers from the floor - these will significant reduce structure borne sound transmission, leaving basically all sound transmission via air (which sucks for sound transmission) until it hits your mass boundaries and sound attenuation devices.

endorka wrote:Source of the post my understanding from the builds of others is that 60dB of full audible spectrum reduction is quite challenging to achieve, particularly when retrofitting a domestic property constructed on a single slab.

Hi Jennifer, I'm aiming high =-) There are two separated foundations for the front and back of the house.

Cheers, Greg

gullfo wrote:Source of the post no, put the foam on the block/concrete. it's just part of the exterior boundary.

Hey Glenn, I was referring to the air space side in between the walls.

the interior wall and frame should have the normal wall (ceiling) insulation which can transcend the "air gap" as the insulation is effectively the "air space" anyways. just avoid excessive compaction on the insulation to avoid coupling the exterior and interior walls. do nto use foam in the interior wall/ceiling system. the foam is ok for thermal but not acoustics.

Very good then Glenn, Thank you. This is what I was thinking
download/file.php?mode=view&id=8092

yep, but i might directly attach the steel to the wall so it could also provide a connect point for isolation brackets.