John Sayers' Recording Studio Design Forum Archive

I moved into this house 9 months ago and ready to take on the decoupling process for a live drum room for recording and videoing . I have a lot of obsticals to overcome and looking for advice. I’ve been doing a lot of research but need nudging in the right direction. Please help. My main objective is sound isolation. Neighbors house is 23ft away and would like to be able to record drum tracks at 9 or 10 at night. The room is in the basement with 3 concrete walls, concrete floor and the house is all brick. Room size is 15’ 8” x 16’ 4”. Above the drum room is the kitchen with a ceramic floor. The house seems very loud. I set up the drum kit and did a decibel reading.  
108.8 decibels in drum room
90.6 decibels outside house toward neighbors house  6 ft away 4ft high
80.4 decibels upstairs kitchen table
76.8 decibels master bedroohm opposite end of house. Door was closed

   Still researching hvac system. There is storage under the stairs (see pic) thinking baffle system or a separate system. I can pull a 5" duct line from our laundry room upstairs that we really don't need. its very small. I've had it shut for quite some time just to see. This is a subject i still need to further investigate and see what my options are. Ive also seen some baffles where they pull air from the room next to the studio.


    As I start this project one of my first question is, on top of the 3 concrete foundation walls, 2 where the Posi Joist rest on the 2x4. There are big gaps/ voids. What do I do here? Foundation walls are 8” thick and the 11 1/2”  Posi Joist pocket above the foundation seems thin in comparison. Above one of the foundation walls, it has only 1/2” drywall with thin insulation separating the new drum room and the bottom 8” of garage wall.  Might as well have a 8”x 16ft open window. Do I add two layers of 5/8 drywall, using green glue between layers. Not sure what to do with the 11/1/2” pocket above the foundation walls. since I have 3 concrete walls that will be my outer leaf. Do I need to put up a 2x4 wall frame and attach it to the concrete wall or posi floor joist above and the concrete floor? if so what is the purpose of this wall as opposed to just leaving a space before putting up my decoupling wall with the two 5/8 drywall leaf? I had trouble finding pics of concrete walls with the decoupling wall and how to go about it. I understand if it was just a normal framed outer wall.

My ceiling might be my biggest problem. My floor joist are Posi Joist. good for building but not good for what I want to do here. Im looking for suggestions on putting up two 5/8 drywall layers to the underside of the upstairs floor for mass. The Posi Joist doesn't make it easy. To Decouple the ceiling from the joist do you suggest the Rc2 channel or the Risc-1 clips with the 2 layers of 5/8 drywall?

other notes:
I will be using video screens instead of glass for the live room. I will be shooting lots of videos
Green Glue between all layers of 5/8 drywall

This is just getting off the ground so please point me in the right direction. The shelves will be coming down this weekend and looking forward to your advise before start making it air tight. Thanks !!

better pics of the drawings.

Hi. Please read the forum rules for posting (click here). You seem to be missing a couple of things!

- Stuart -

As Stuart pointed out, please read the forum rules and follow them. Thank you!

Note: Because it would take a ton of detail and time to give you all of the possibilities of answers to your questions, often responses to your questions come with more questions. This will force you to think about why you are doing certain things and then do research on the forum to find out possible solutions. From there, you can come back to the forum members with more detailed questions that we can actually give you answers to.

Above the drum room is the kitchen with a ceramic floor. The house seems very loud. I set up the drum kit and did a decibel reading.
108.8 decibels in drum room
90.6 decibels outside house toward neighbors house 6 ft away 4ft high
80.4 decibels upstairs kitchen table
76.8 decibels master bedroohm opposite end of house. Door was closed

What did you do a measurement with? Fast or slow? A or C weighting? You should have done them slow and C weighted.

Still researching hvac system. There is storage under the stairs (see pic) thinking baffle system or a separate system.

By "baffle system" do you mean zoning your rooms off your existing air handler unit? If so, chances are, your current unit will not handle the extra load. A separate system would probably be the best. You could go ducted or ductless.

I can pull a 5" duct line from our laundry room upstairs that we really don't need. its very small. I've had it shut for quite some time just to see.

I wouldn't recommend this. Your laundry room needs good ventilation not only for comfort but for things like mold. I wouldn't steal that. Plus, for the size of your rooms, 5" is far from large enough. See my last comment.

This is a subject i still need to further investigate and see what my options are. Ive also seen some baffles where they pull air from the room next to the studio.

Again, your HVAC system was design to have supplies and returns in specific places for a reason. Unless you have some small supplies or returns in your studio rooms locations, don't touch them.

HVAC is a huge subject. I would suggest googling some handbooks and read them. Realize that when you read the HVAC stuff online, it's the theory about sizing ducts and how systems are designed to follow codes in the ASHRAE handbook. Studio HVAC is a different beast. The theory still applies, however the silencer methods are way different and unlike homes, our studios are hermetically sealed and insulated like crazy. We also are creating more latent and sensible loads than someone watching TV or hanging out in their bedroom would.

on top of the 3 concrete foundation walls, 2 where the Posi Joist rest on the 2x4. There are big gaps/ voids. What do I do here?

Your pictures are so small, I can't really make out what's what. Either way, basic studio building techniques should apply and should answer your question here. Seal it with caulk (and backer rod if necessary). Make sure any rim board that is there is beefed up. Add MDF or drywall layers to it with Green Glue compound between the layers. Seal every crack. After that, fill any voids with insulation.

Above one of the foundation walls, it has only 1/2” drywall with thin insulation separating the new drum room and the bottom 8” of garage wall. Might as well have a 8”x 16ft open window. Do I add two layers of 5/8 drywall, using green glue between layers.

Yes. You need to add that mass. Sounds like you understand the concept!

Not sure what to do with the 11/1/2” pocket above the foundation walls.

As long as the exterior sheathing of your outer leaf has the surface density needed, you're good to go. Make sure everything is sealed and completely fill between your outer and inner leaf with insulation.

My ceiling might be my biggest problem. My floor joist are Posi Joist. good for building but not good for what I want to do here.

What is wrong with them? They're pretty standard. You shouldn't need them to do anything more than they currently are. Your new ceiling will live below the joists.

The only issue I see is that you have duct work running through the joists that will need to be boxed in. That is a big job.

Im looking for suggestions on putting up two 5/8 drywall layers to the underside of the upstairs floor for mass.

This will be one of the hardest parts of your build as it's all over-head work with heavy materials.

Do it like this:

To Decouple the ceiling from the joist do you suggest the Rc2 channel or the Risc-1 clips with the 2 layers of 5/8 drywall?

Nope. This honestly won't create enough isolation to do what you want with your drums. The only way to achieve enough transmission loss to contain the energy created by an acoustic drum kit will be building a room in a room. Only touching one another through your concrete foundation. If you don't do this I can confidently say that you will spend a ton of time and money only to end up with sub-par results and you won't be able to play your drums at the hours you wish. In short, you will have wasted your time and money.

I will be using video screens instead of glass for the live room. I will be shooting lots of videos
Green Glue between all layers of 5/8 drywall

No windows makes things a lot cheaper and easier to build.

This is just getting off the ground so please point me in the right direction. The shelves will be coming down this weekend and looking forward to your advise before start making it air tight. Thanks !!

- Don't underestimate the importance of HVAC. The learning curve for HVAC is about as steep as learning about acoustics. Having said that, the design of HVAC takes about as long as the design for the rest of your studio. You can't add or even modify HVAC once your studio is built, so design and build it right.

- You can't effectively design and build a studio without 3D modeling it. We've seen it countless times on the forum where people try, and they screw up, and then they disappear, never showing the end results of their studios. Therefore, download and learn SketchUp Make: https://help.sketchup.com/en/downloading-older-versions

- Sure, tear out the shelving and even start beefing up your rimboard, subfloor and sealing the hell out of it. Stop after that though because until you have your design 100% done, there really is no point in building anything else. Chances are you are going to have to move some existing infrastructure. Don't waste your time and money. Take the time to learn the craft, design it, keep posting here and ask for advice or even a second set of eyes. After everyone on here, including you, are excited about your design, THEN buy some wood and start building.

I can't stress enough how important it is for you to download and read this book:
http://www.roletech.net/books/HandbookAcoustics.pdf

Once you do, you'll have a great grasp on things. There are lots of topics not covered in that book such as the current HVAC silencer boxes being designed on this forum, or John Sayer's inside out construction technique. But these are all things you can find by reading some design or build threads as well as asking questions. We are all here to share what we know. We like helping.

Again, just read the forum rules and follow them. Post lots and keep us in the loop. Even if it's not asking questions. We like to read progress stories, see design pictures, and of course, in the final stages, build pictures!

Greg

Thanks Greg appreciate your patients. I have lots to learn and will read your forum rules, my bad lol. I have read Rod Gervis, home recording studio twice now and will definitely read the links you suggested. Mass Mass Mass. Two leaf good, four leaf bad. Looks like my hvac will be a separate unit, and will look into the ceiling joist being seperate. I have lots to learn and thanks again. I will start on my two 5/8 drywall layers under the upstairs floor and stop there till i get my thoughts and ideas together. You guys rock !!!

I will start on my two 5/8 drywall layers under the upstairs floor and stop there till i get my thoughts and ideas together. You guys rock !!!

You should probably start by reading the forum rules for posting (click here). You are still missing something!

- Stuart -

I have a question about one of my Rim Joist. I have a 4 3/4 x 1x3/4 Void. The open web truss only rest on the sill 2" and kisses the metal brick flashing,( which is loud if you tap on it) leaving this void. The 8" concrete foundation wall shares the outside patio concrete floor along with the inside truss. So after i seal the Rim joist with Green Glue acoustic sealant. What do I fill this void with? It runs the full 16' 4". I know after I fill the void and make it flush with the metal flashing (void is 1 3/4 deep) that I should add at least two 5/8 drywall with GG in between and caulk all cracks with the sealant. Im just not sure what to fill this void with. Should I use Owens Corning Polystyrene insulation board thats an 1 1/2 thick and then start adding drywall or just use layers of drywall to build up this void?




The opposite Rim Joist end sits on a 8" concrete foundation wall as well. Its in a 10" pocket up against my garage drywall so I will seal all cracks with sealant and then start layering my two Drywall panels with the GG.

The wall running parallel with the truss sits on a 8" concrete foundation wall and has a styrofoam type insulation before the outside brick. Im assuming the same drill. Seal with acoustic sealant and start adding my drywall layers.

Thanks for any advice.

Gregwor wrote:

Im looking for suggestions on putting up two 5/8 drywall layers to the underside of the upstairs floor for mass.

This will be one of the hardest parts of your build as it's all over-head work with heavy materials.

Do it like this:

rsz_supports_for_drywall_between_floor_joists.jpg

I just did this in my basement. I wouldn't necessarily call it "hard", though it is kinda of a PITA and extremely time consuming just because of the number of cuts you have to make. If you have hardwood floor overhead (as I do) then you may have a bunch of nails coming through, which you do NOT want to back out by pushing into them with drywall. In that case, you can put a layer of cheap 1/2" styrofoam sheeting between the subfloor and the top layer of drywall.

Some suggestions to make the process easier but (somewhat) slower: cut the drywall the short way, so you're only working with 4' sections instead of 8' sections. And if you can make it work with the way your basement's built, put it up one layer at a time - this takes 2x as much wood and nails and almost 2x as much time, but is a LOT easier to manage since it only involves lifting 1/2 as much weight at any given time.

Build a couple of deadman braces out of scrap lumber. You will need them.

It's kind of hard to tell from the pictures how much plumbing and ductwork you have running through those joists. IME, that's gonna be your biggest ball buster, but fortunately, it looks like you have enough clearance around whatever is there.

-Dan.