John Sayers' Recording Studio Design Forum Archive

As I eagerly await hearing back from Stuart

Still here! Just got lots on my plate right now. But Glenn and Andre and Brien are on your thread, so you don't need me too much!

Since this room will be closed off from any natural ventilation ...

You WILL still need to ventilate that space! It will have two totally airtight, hermetically sealed envelopes around it, and it will have people inside it. People need to breathe.... draw your conclusions: You have to have ventilation ducts. Two of them. One brings fresh air in, the other takes stale air out. They need to be lined inside with acoustic absorption, and isolated, or course, with silencers in-line, and a few extra 90° bends. But you do need them.

Although we don't usually get more than a few weeks of hot summer

You will also have a couple of rather thick layers of thermal insulation around that room, plus a large sealed air gap. And you will have equipment and people inside, both of which happen to generate heat... More conclusions: you need good cooling (in addition to the ventilation), and it needs to be dimensioned correctly for the size of the room and the amount of heat that will be going into it from people and equipment.

First ... it was the proverbial ... "deer in the headlights" gaze
then followed the room, bursting into laughter.
I took all the personal, slanderous 'you're crazy ... outa you're mind, comments in stride

Maybe I'm speaking out of turn here, but honestly, if that was the attitude of my contractor, I'd dump him on the spot and look for another one who DOES understand a bit about acoustics, or at least is prepared to learn! I don't think I'd be too keen on using a guy who does not get even the basics of what needs to be done...

I'm guessing I'd need the advice of a structural engineer ?

Yup! Most definitely. You'll be hanging many hundreds of pound of stuff above your head, and putting hundreds more standing up around you. It has to be done safely.

I guess that Stuart must be busy on something else

The initial design from Stuart was a 3 leaf wall.

Nope! No three-leaf in there! Take a close look: It's two leaf all around. Some are inside out, some are normal, but they are all 2-leaf.

These guys also do electrical ...

Tell them that you need star grounding, with a single excellent grounding point, and separate circuits for lighting, HVAC, audio equipment sockets, and general sockets. Star grounding is important. they should know how to do that. They also need to be aware that they CANNOT make any holes in your walls! You are going to huge efforts to create a massive airtight barrier around you. They are not allowed to go punching holes in that! If they do, they destroy your isolation. All of your plugs, lights and wiring should be surface mount, if possible. Of course, there will have to be at least one hole somewhere, to bring power in to the room, and you might need to have a couple more for whatever reason, but those will have to be done carefully, and then sealed with putty packs, or some other system that replaces the lost mass and the lost hermetic seal... Hopefully, they will understand that this is not a normal type of electrical installation, and nor is it a normal type of HVAC installation: There are other things they "must" and "must not" do with the HVAC... They need to be aware of all this upfront, before they quote.


- Stuart -

(PS. I just noticed that others have already answered some of the other points already...)

AVare wrote: And just for fun:

...
IR-802

That should give you some reading material for the evening.

Andre

A comment that isn't really pertinent to this thread, but I just noticed some interesting stuff on IR-802, Andre. Figure 7 and figures 18, 20, 23, 24, 25 and 30 ... If anyone ever needs proof why it is a BAD idea to float a floor without doing it right, there you have it! As much as 10 dB reduction in TR, across a broad range of lows and even mids!

Thanks, Andre! I hadn't seen IR-802 before, but it is very interesting.


(Even more convinced than ever about floating...)

- Stuart -

Hi Stuart !

GOOD to hear back from you ! I hope you're having a good 'busy' !

I can certainly understand how schedules & workload change. I was a little hesitant till now ... not wanting to have the 'too many chefs in the kitchen' syndrome. Of course, the group of Experts here already understand that ... I just needed to hear from you first, but please, don't be a stranger !!! I value your messages

And then Glenn steps up, and knocks me out with a great plan ... along with renovation/mods to the current structure.

This new CR is coming at a type of crossroad for me. After some 30 years working professionally as an engineer & producer, I stepped away to ad-junc at a University [teaching Analogue/Digital Rec Tech]. Without boring everyone on the details, the music scene changed and the digital rev was on. I'm NOT one of those 'digital' haters ... but I much prefer the workhorse analogue hardware. I've had several DAW systems over the years, and have purchased alot of 'high-end' digital plug-ins ... but I was not satisfied with the final sounds [when push came to shove ... I heard this 'plastic' type sound
Well, some new things have developed software wise that has re-sparked my Love ... and since I HAD to tear out my old room anyways ... I want to put a new room in my house, if anything, but just for my own work and enjoyment. There are no plans to do any recording. I will focus solely on mastering, restoration and the possible DAW mixing.

Doing this without disturbing the rest of the household, in an accurate room [given limitations] is what you guys have been guiding me toward. I also refer to Rod's invaluable hymnal 'Build It Like the Pros'.

ahhh ... probably bored everyone to tears. My apologies.

Got my contractor coming ... would like to ask some questions after!

BTW ... my description of the contractors initial response was more to add a little humor to the thread [thus my short-lived career as a comedian].

Thank-you

Back again.

First ... Thank-you Stuart for correcting my 'leaf' claim. I messed up on the terminology in a big way! Thanks for spotting and correcting. More on this at the appropriate time.

What I've been focused on is the current structure ceiling [floor above].

I've put together a few images, and have gather structure data to give to the structual engineer.

I'd like to post that data here so that it can be available.

---
The Control room area is approx. 14' x 17'

Floor Joist: 1-1/2" x 9" across a 14' span. [13 pieces] 16"oc.

Center Load Bearing Beam: 4 - 1-1/2" x 7-1/4" = 6-1/2" x 7-1/4"

2 3" metal support poles.

Cross beams 1-1/2" x 2" in the middle half of this room

Upstairs flooring - 3/4" hardwood
Sub-floor - 1/2" plywood ??? [according to the house plans]
-------------------------------------------------------

Based on initial design specs:

[*** All drywall spec'd @ 5/8" thickness to start]

The 1st layer of drywall inserts would require 9 sheets of 4'x8' - 5/8"
2nd layer - 9 sheets.

The new main ceiling [2-layers] [8 sheets/layer] = 16 sheets

ceiling drywall Total = 34 sheets

1" rigid foam inlay = 9 sheets 4x8

1x3 furring strips
caulking
Green Glue

*** note ***

All sheet calc are estimates. Have NOT accounted for wasted pieces.

What other info do we need for structure engineer?

------------------------------------

I've attached some pics of what the 1st treatment might be according to what has been talked about.

Does this look correct?

Thanks

great ... the SU file is too big

let me see what I can do to attach that.

that looks correct

Was not able to get the SU file posted here So I just labeled the image for now.

Here's a question ... if we $ DONATE $, are any other options available [like larger file uploads] ??? just wondering.

I sent current area build info for structure analysis. Maybe I'm being overly cautious, but from my early calculations, it looks as if 34 sheets of 5/8" drywall would be hanging above my head. According to United States Gypsum (http://www.usg.com), "4' x 8' x 5/8" thick sheet weighs about 70 lbs." That = 2,380 lbs being added ... NOT including additional lumber, etc. Sure this is spread over a 14' x 17' area ... so ... I don't know if that's crazy, or should I be going with 1/2" drywall instead.

Also, should I use GREEN GLUE between those double layers in the joist ?

The carpenter that stopped in to look at the job mentioned that using something 'heavier' than 1x3" furring strips would add to the joist strength [maybe 2x4 ???].

In Rods' book, I don't see mention of what type of caulking to use up there. Is it regular painters caulk ?, or silicon caulk ?, or should I be using the acoustic sealant from that GreenGlue company?

Sorry for all the 'stupid' questions... just thinking about where I have to get materials from, how much, and what type.

Oh ... the rigid foam. At Home Depot I saw 'R-4 FOAMULAR 250 - 3/4" ', or ''R-4 FOAMULAR 250 - 1" '. The nails stick thru about 1/2" ... they CAN be bent back flatter. Was wondering if this is the type of material I should be using first up there [without causing other issues]? Or would something be better?

Hope to hear back soon regarding structure load capability ... and, again, THANK-YOU for your patients and understanding/guidance on this 1st critical treatment. I only have one shot to get this right

On your first set of drawings I'm curious as to why you decided to go with hat channel and RSIC clips, instead of with interleaving new joists between the old joists, as suggested originally. You will lose a bit of height like that, as well as some isolation. And in any event, as far as I know the channel should run perpendicular to the joists, not parallel to them.

or should I be going with 1/2" drywall instead.

Bad idea! The isolation properties of 1/2" drywall are nowhere near as good as for 5/8". Worst case, just use larger joists for your inner leaf. (assuming that you decide to abandon the hat-channel idea, and go back to the original interleaved-joists solution).

Also, should I use GREEN GLUE between those double layers in the joist ?

If you can afford it, then absolutely! It will improve the low-end isolation quite a bit. And low end is the hardest to deal with anyway: any help you can get is worth it, provided it doesn't blow your budget.

The carpenter that stopped in to look at the job mentioned that using something 'heavier' than 1x3" furring strips would add to the joist strength [maybe 2x4 ???].

Technically, those are cleats, not furring strips. And you'd have to check with your structural engineer to see if their contribution is worth anything. Generally, cleats are much smaller than what you show: they only have to hold small pieces of drywall in place up against the sub-floor above. AFAIK they aren't' really meant to provide an structural support to the joists. Maybe Brien can comment on that.


- stuart -

"Here's a question ... if we $ DONATE $, are any other options available [like larger file uploads] ??? just wondering."


You get the continued unrestricted use of Mr. Sayers forum, often his help but always his talented Mods assistance....and page upon page of technically correct information.


Your clips and hat track should run perpendicular to the joists and not installed directly to one individual joist per run.


What was that worth?

xSpace wrote:"Here's a question ... if we $ DONATE $, are any other options available [like larger file uploads] ??? just wondering."

You get the continued unrestricted use of Mr. Sayers forum, often his help but always his talented Mods assistance....and page upon page of technically correct information.

Your clips and hat track should run perpendicular to the joists and not installed directly to one individual joist per run.

What was that worth?

The advice, guidance, and KINDNESS has been priceless !

I made my '1st install' donation [still putting my build budget together, and this forum will be included]. sincere thanks!

Hi Stuart !! Thanks for the RED FLAG ! regarding those clips. I think I was just getting carried away with SketchUP. I was attempting to diagram out for a carpenter a scenario.

I absolutely concur that the clips as shown would lower the ceiling way to much. [these were the only clips I found in the SU library.

Importantly, I need to consolidate into a single overall design. Primarily the 'shell'.

Just in observation [and in NO WAY a criticism], Glenn's design [with the symmetrically boxed in back wall] looks great and very do-able. His initial drawing showed a single wall, whereas you're design had 2 walls. I see where you placed the new ceiling beam, resting on TOP of the inner wall, straddled between the current joist above. Using THAT concept takes half of the material weight OFF the structure joist and moves it to the new build. [As Martha would say, 'this seems a good thang'.] Construction-wise, I think I could build this easier.

Glenn, please correct me if I'm wrong ... I'm thinking that you placed a single wall to 'example' the design. I'm having to compare back/forth between v7 & v8 drawings. I see that a second outer wall could/should be added [?]. And according to Glenns' design, we'd have an interior room size of: 12' 1/2" x 15' 4-1/2" with a ceiling height up to the bottom of the 7' high joist, with 2 layers of 5/8" drywall suspended across NEW ceiling joist, interleaved between the old joist, and resting on the top of the inner wall sill. That would put the CR ceiling at just around 6' 10". Are these room ratios still good?

Again, please be assured there is NO negative in my comments above. I looking to consolidate the final design so that I can begin a 'materials needed' list to get the budget into better focus. Things like walls being 2x4 24"oc is what I see in Glenns' design, the new ceiling rafters width and span is also to be determined.

I can really appreciate the comment that 90% of this effort is where we're at now.

Once again ... big THANKS for hand-holding me through this, and slapping me around when I go astray

Sincerely,
RJHollins

in my design, the new inner walls are isolation walls. you already have existing walls on 2 sides and only need to add interior walls to hide the backs of the new walls on the window and door sides. the ceiling is isolated from the existing floor joists using isolation brackets and hat channel. no new ceiling joists the new isolation ceiling is supported by the existing floor joists. no attaching the new walls to the beam either. basically l left about 2 inches around the new isolation walls which gives you about 6.5" of air gap on the outer walls and 9" between the interior walls. the isolation walls are supported by isolation mounts (like Mason Industry WIC or RISC mounts) to keep them stable and decoupled. effectively the main flanking path should then only be your basement floor.

Hi Glenn,

Say ... I think I need to post a SketchUP file that will better identify the house layout.

Due to the file size restriction, I think some pertinent concerns will be better identified, I just could not fit them in to show what I have to deal with. We've been mostly focused on the area above the CR, but I also have issues outside this room ... [probably like most in-house builds.

Let me put together something and post it to be clear ... 'cause, Lord knows, my brain has been scattered dealing with doctors & hospitals for Ma. With the 'shingles', she went in Friday morning for double knee replacement So this has been a stressful time, and my posts here have been scatter-brained at best

Back as soon as I can.
thx

Back from a productive meeting with my financial coordinator and my contractor. [also a great dinner]

I also tried to do a SketchUP of the house layout. Man, do I need work on SU skills !

This is a difficult to describe layout, and a challenge for an SU newbie. It is referred to as a 'split-level ranch' design.

Down here in the basement, the ambient noise is easily 65 dB [mostly due to dehumidifier]. But I also have washer/dryer, hot water heater, gas furnace and a sump pump. When all these bad boys are working, its' like being in a factory! In a quiet time, I'm reading 47 dB.

Up the short stairs from the basement is the family room, were people could be reading/studying, or blasting the tv.

We've already talk about the upstairs, which has the LV,kitchen, dining room all directly above the basement.
Above the family room is the bedroom area. Quite the layout.

But as may be more apparent ... this CR is in a hostile area Not only do I need to minimize CR sounds getting out and bothering Family room and upstairs ... I have a jungle of sounds right outside the CR.

This be the reason I thought double walls would be the minimum. The current 'lack of isolation' clearly allows the dehumidifier to be heard in the kitchen [something I want to correct by first throwing this brand new unit off the top of a building]

Just wanted to put this out there.

Tomorrow I may hear from the struct-eng.

[time for me to get back to read Rod ............

as far as i can tell we're all in agreement in needing the isolation...

RJHollins wrote:Down here in the basement, the ambient noise is easily 65 dB [mostly due to dehumidifier]. But I also have washer/dryer, hot water heater, gas furnace and a sump pump. When all these bad boys are working, its' like being in a factory! In a quiet time, I'm reading 47 dB.

Up the short stairs from the basement is the family room, were people could be reading/studying, or blasting the tv.

We've already talk about the upstairs, which has the LV,kitchen, dining room all directly above the basement.
Above the family room is the bedroom area. Quite the layout.

But as may be more apparent ... this CR is in a hostile area Not only do I need to minimize CR sounds getting out and bothering Family room and upstairs ... I have a jungle of sounds right outside the CR.

This be the reason I thought double walls would be the minimum. The current 'lack of isolation' clearly allows the dehumidifier to be heard in the kitchen [something I want to correct by first throwing this brand new unit off the top of a building]

Just wanted to put this out there.

Often in a hostile environment, folks that do this type of thing will consider the parts that are creating the noise and make adjustments to these appliances or what-have-you in order to reduce the impact that can otherwise reduce the overall effectiveness of the proposed isolation requirements.

Some considerations might be:

A vented room/boundary wall around the washing machine/dryer area. This would include the ceiling that seems to be currently exposed. A lot of focus can be placed on the overall environment in an attempt to reduce, when an ad hoc process may better suit the case.

Creating a decoupled base for the washer/dryer can reduce the impact of both and wouldn't be that difficult to achieve.

Then there are solid doors and seals for any access doorway leading into the basement proper. Assuming that required ventilation will not be affected by the installation of these, even still, ventilation can be achieved in other ways.

Directly to your overhead concerns. If you are going to use clips/hat track then you can have your installation guys remove the current diagonal bracing in one bay at a time. Install the 3/4 inch exterior foam sheathing/mass and cleats/caulk, etc. etc. The easiest way, again, if you are using clips and track (Versus a separate framed ceiling) will be to reinstall blocking, you have 2X10 Douglas fir existing, 2X8 may be an almost exact fit, after everything is said and done.

To over stress the importance of the blocking could only be done to someone that understands why it is there to begin with. It has a two-fold purpose one being to spread the flexing ability across all the joists rather than having each individual joist try to depend on the overhead nailing/plywood. Secondly, and most importantly, to reduce the potential for roll over of the joists under impact or even day to day dead loading.

Diagonal bracing is difficult to re-install in a joist system, blocking is easier, nailing is important, staggered blocks are easier to install than one straight line/pattern.

Thank-you Brien for your insights and explanation. It really helps ! I've had some experience with building, but I'm not a professional in that field, so even some of the terminology requires me to 'look things up', and/or ask those with the knowledge.

Wednesday the structural engineer is coming over to evaluate what I have, and what plans are in the works. He is very knowledgeable. He was involved with structure eval on both of my brothers' behemoth homes. Not sure that the original architect's designs might have been 'weak', but the changes he brought have been flawless. Anyway, he's been with my youngest brother [contractor] for years. I look forward to seeing him on this project. Then I'll know what design to proceed with.

There are things I really like in both plans sent from Stuart and Glenn.

Stuart got me a slightly bigger room [although he said a slightly better one would reduce the size]. His dual 2x4 walls on the side and front of the room was in-line from the articles and Rods' book, and resting the new ceiling on top of the inner wall sill coincided with my early thoughts, so I was like 'oh, cool" that was a good idea. Especially since the floor above me squeak and cracks when people walk, and when the kids come over, running around, the pounding shakes the basement. So I'm wanting to lean toward Stuarts concept.
Then, Glenn steps up with his great design, creating symmetry in the back of the room, allowing for corner chunky traps, and basically a sensible design and build back there that meets approval ! [that is huge]. I'm still am not quite understanding why the single wall design all the way around. I now see, from reading, that we want to avoid the 'triple-leaf' with the concrete walls ... but for the 2 other walls, having a drywall finish to closing them up, especially where the sump pump is, that a dual wall with air gap, insulation, and 2 layers 5/8" on the inside of the room, a 1 layer on the far outside wall would have been recommended. Be able to enclose the 2 metal support poles would have been a nice, cosmetic touch. So as of right now, I must be missing an important point

The layout for the door and the acoustic treatment is invaluable.
However, the planned 'window' is still being mulled over ... maybe a type of surveillance camera/monitor would be a better idea, both construction-wise and cost.

Without stepping on toes, or coming across as an ingrate ... maybe a blending of the designs would be ok ?

Don't know yet ... BUT ... I'm gonna know more tomorrow on the 1st step of operation 'Ceiling Beef-UP'.