I don't understand how the joists would work, do you mean a truss of some sort? Or do you mean adding a center beam and running boards up to it at the peak? What kind of truss spans 40 feet and is only 1 foot deep on a 4-12 pitch?Huh? :shock: :?: Sorry, but that makes no sense at all! The final ceiling will be at exactly the same height, no matter how you support it. The air gap and mass both MUST be the same size, regardless of the way you support it, if you want to get the same TL. It's a simple mathematical equation, based mostly on mass and air gap. You cannot beat the math and the physics by resorting to a different method. What defines the TL is mass and air gap. Therefore the final ceiling for any given TL number will ALWAYS end up at the exact same height. Like Brien said: it makes much more sense (and will most likely be cheaper) to just put joists across the top of your inner-leaf walls, and hang your ceiling from that. - Stuart -I want to avoid another framed ceiling, i would lose too much height.
Exterior wall concept
Originally posted at johnlsayers.com, topic 15096.
I have read this post several times and still can't quite 'get' where you are coming from. Ok i am trying to learn here. I notice some long time pros around here tend to really breeze over the details of some pretty complicated concepts. And that is fine, i don't mind getting a hint then doing my home work. But i at least need enough understanding to know what to do my homework on. I understand stc is not the final frontier. I understand the point about keeping a consistent shell, wall and ceiling. But the westerner thing???? Like the Yukon is in Canada, in the west, you know that right? The over stressed over used thing with the spelling things at the end make no sense to me. Is it flippant? Sarcastic? What does it mean? I'm sure you guys hear many of the same questions over and over, but try to be patient please. Again, I'm all about doing the homework if i can get a lead in the right direction. Thanks for helping out :)If an arbitrary number, or a number assigned to a specific assembly rather, is assigned then it is assigned only to that assembly. In your case the ceiling/roof has been given a number based on someones educated estimate. The walls have been given this same number? In order for this to be truly the...well lets forget stc and focus on the isolation gauge of transmission loss, complete environment you are wanting, and you have spent much money on this project, you have to keep in mind the mass-air-mass, which is the decoupled room-in-a-room environment, so many westerners attempt to gain. Doing one thing with the ceiling and another with the walls and assuming that somehow they have no relation to one another, is missing the big picture of this much over stressed always over used room in a room environment, that what you seem to be suggesting, is not.
So to summarize, you're considering using isolation clips on the ceiling to preserve height, ok. You want to use a separate interior wall in a double leaf configuration, ok. You will be using green glue between the GWB layers, ok. You will use some form of mass on the exterior to beef up the walls, ok. You're in the middle of the Yukon territory about a mile from the nearest other human? I would be surprised if you have a problem for isolation (edit - on the outbound side at least)
What you are suggesting is a ceiling assembly and a wall assembly. What you should be trying to approach is a ceiling/wall assembly that has the same air cavity rather than two assembly's that have an individual air cavity per assembly. You tell us what is your next move...to use clips and hat track on the ceiling,,and then how will the wall framing fit into this?...caulked up to this decoupled ceiling? The airspace should be contiguous...the framing should be without attachment from one to the other.I understand stc is not the final frontier. I understand the point about keeping a consistent shell, wall and ceiling. But the westerner thing???? Like the Yukon is in Canada, in the west, you know that right? The over stressed over used thing with the spelling things at the end make no sense to me. Is it flippant? Sarcastic? What does it mean? I'm sure you guys hear many of the same questions over and over, but try to be patient please. Again, I'm all about doing the homework if i can get a lead in the right direction. Thanks for helping out :)
What about a 1-2 layers of drywall on the trusses, clips/HT on top of that layer and then 2 layers on the clips/HT, Even thought the airspace isn't the same width as the walls then i would have one at least.
I could lay some R8 pink insulation inside the hat track and first layer(s) too with a light string grid system.
If I understand you correctly, you are suggesting attaching drywall directly to the trusses, then putting RSIC clips plus hat channel directly on the drywall, then more drywall on top of that? If that's it, then don't do that! The thin air gap between the two "leaves" means that your MSM resonant frequency will be VERY high, and therefore your isolation will be low You should always have at least 4" between your leaves. Any less than that and you start compromising your isolation. The smaller the gap, the worse it gets. - Stuart -What about a 1-2 layers of drywall on the trusses, clips/HT on top of that layer and then 2 layers on the clips/HT, Even thought the airspace isn't the same width as the walls then i would have one at least.
Ok, thanks for clearing that up. It kept coming back in my brain as an option.If I understand you correctly, you are suggesting attaching drywall directly to the trusses, then putting RSIC clips plus hat channel directly on the drywall, then more drywall on top of that? If that's it, then don't do that! The thin air gap between the two "leaves" means that your MSM resonant frequency will be VERY high, and therefore your isolation will be low You should always have at least 4" between your leaves. Any less than that and you start compromising your isolation. The smaller the gap, the worse it gets. - Stuart -What about a 1-2 layers of drywall on the trusses, clips/HT on top of that layer and then 2 layers on the clips/HT, Even thought the airspace isn't the same width as the walls then i would have one at least.
Clips and track on the empty trusses would be the way to go...then install the sheetrock on that assuming the trusses can accommodate the additional load but a framed ceiling on the interior walls would be ideal.What about a 1-2 layers of drywall on the trusses, clips/HT on top of that layer and then 2 layers on the clips/HT, Even thought the airspace isn't the same width as the walls then i would have one at least. I could lay some R8 pink insulation inside the hat track and first layer(s) too with a light string grid system.
I should be able to do my sound tests this week. That should help decide on the framed ceiling or not. In the mean time, any suggestions for a simple interior roof framing style, i think i could stand a couple support posts in the room as i am sure that would be required if i want to avoid trusses, which i do. This would only be put up btw in the large recording space which is roughly 36' long and 40' wide. I will look into the truss load for the clip/track option too.Clips and track on the empty trusses would be the way to go...then install the sheetrock on that assuming the trusses can accommodate the additional load but a framed ceiling on the interior walls would be ideal.What about a 1-2 layers of drywall on the trusses, clips/HT on top of that layer and then 2 layers on the clips/HT, Even thought the airspace isn't the same width as the walls then i would have one at least. I could lay some R8 pink insulation inside the hat track and first layer(s) too with a light string grid system.
Maybe engineered beams might work for those spans? (Not sure. Just throwing out wild guesses.)
- Stuart -
Sound Test done!
Let me know if this isn't comprehensive enough i have the gear one more day.
I used 2 Yamaha wedges with 15" 's and horns. I place them inside the center of the building which has all door openings open and one big garage door type opening open still. The rest is framed and sheeted with 1/2" osb and roofed with asphault/fiberglass shingles. Windows are in.
I did a sine sweep from 25-500hz at around 110-112 db on the sound meter about 2 feet from the speaker. Then i went to the closest edge of the property and measured.
The highest peaks on the sweep reached 62 db on the meter.
Then i played "Godwacker" from Steely Dan's "everything must go" which has fantastic tight and proud bottom end at 112 db (the speakers couldn't handle much more it seemed).
Then i went to the closet potential site for a house on the neighboring property and neither the highs or lows made the lowest setting of 50 show on the db meter.
Also from an ear standpoint i noticed the bottom didn't travel well at all either with the sine or the music, just the bouncy highs mostly. It was calm and quiet as it gets here today, only other factor bring the foot of snow on the ground, none in the trees.
Oh, it was about -7 Celsius whn i did the test.
How helpful is any of that?
None really for me.
When I was testing my room I couldn't get a reading outside of the room three feet away with a digital meter....and it sounds like you are farther than that...but you did say you had all the windows and doors open....so...
Isn't the point to see how far the bass travels and how much of it?None really for me. When I was testing my room I couldn't get a reading outside of the room three feet away with a digital meter....and it sounds like you are farther than that...but you did say you had all the windows and doors open....so...
That is why i did the testHow much isolation do you need? This is the first question you should answer when trying to figure what type of isolating wall system you should build.
agreed, having an understanding of how your terrain carries the sound is good. if you get the chance to then test with the doors and windows closed, it will give you some idea of the isolation you have. it sounds like (reads like?) the terrain is covering a multitude of sins so even reasonable isolation on the shell will be good. however, sound escaping your live room (for example) can flank into your control room (and vice versa) via the sound outside so consider that in defining your final isolation target.
Back to the way the ceiling on clips and hat track connect with the inner wall....
Would i be ok to plan to install the whole ceiling- trusses/clips/ track/ 5/8's dw/GG/5/8ths dw throughout, Then later add the interior walls?
Then the ceiling is done while we can get a lift in there.
Could those interior walls with 2 layers of 5/8ths dw be framed up close and the dw layers of the walls caulked with backer foam to the ceiling dw?
The walls would be supported by each other with no top connection, just sides and to the concrete floor.
Thoughts?
layout the rooms carefully and have the ceiling drywall conform to the room layout so you have gaps where you need it to avoid coupling the rooms. the walls, assuming back-to-back could be braced using isolation brackets and anchored, the upper parts could be anchored using isolation brackets to the trusses to add additional stability without being coupled.then your drywall layering and backer rod/caulking would be per normal to achieve the proper seals with limited or no hard contact between the walls and ceiling drywall.
For give me, I thought this was an already built structure....so many posts so little time....Isn't the point to see how far the bass travels and how much of it?None really for me. When I was testing my room I couldn't get a reading outside of the room three feet away with a digital meter....and it sounds like you are farther than that...but you did say you had all the windows and doors open....so...
Here is where i have it to dimension wise. My reasons for these dimensions and layout are mixed. They mostly come from how i like to work, sight lines, what i have read regarding various angle considerations and minimum size recommendations. My goal now is to refine these dimensions down to the inch if possible, inner and outer so as to have the best start with treatment in each room. A couple notes: -The 'Bright room' is something i want to be able to get a BG piano eventually into through double glass doors on the side facing the CR room main window. No i don't have a BG but i may in the next decade or so if the world doesn't end by natural disaster. Also in that room i have collected a stunning array of sweet rocks (shale type) that i would like to run up to 8 ft or so on the back 2 outer building walls(back corner). Initially I intend to use this room for things like acoustic guitars/instruments, vocals, percussion etc. -In the main room i would like to leave space/consideration for a wall or 2 of variable surface rotating panels on the outer walls, those 3 sided triangle things that you spin to your sonic desire. -The storage area is strictly for amp and gear storage and repair. But i am considering adding a ceiling at 7 feet over 1/2 of it and putting a small vocal booth above it looking down into the main room. This would be used strictly for vox isolation when tracking beds. -I would like to explore the LEDE CR. I think i have enough room for one. ? We work in the CR a lot, i have a couple projects where we work almost exclusively in there. So some air in the back half would be really nice. I have left some room for diffusion there. There is a window at 11 feet on the back wall of the CR to consider. - The kitchen/lounge/aux rec room is just that. I would like it to be eventually usable for a secondary iso room. Not super loud sources but things like BU vox or isolated acoustic instruments. There will be too many rattley things in there to put a bass amp or stack in there so i don't want to spend money doing major isolation on those walls to the exterior and the CR. -The bathroom dimensions are totally flexible, it doesn't need to be that big.layout the rooms carefully and have the ceiling drywall conform to the room layout so you have gaps where you need it to avoid coupling the rooms. the walls, assuming back-to-back could be braced using isolation brackets and anchored, the upper parts could be anchored using isolation brackets to the trusses to add additional stability without being coupled.then your drywall layering and backer rod/caulking would be per normal to achieve the proper seals with limited or no hard contact between the walls and ceiling drywall.
So, the above post in mind, can we start with the CR?
What are the concerns with the LEDE approach that i should be aware of?
I have 20 feet of space floor to peak for trapping.
The main issue is that it's about 30 years out of date! :) Seriously, RFZ is a much more common design today (also sometimes called "non-environment", but they aren't really the same thing). - Stuart -What are the concerns with the LEDE approach that i should be aware of?
Pardon me i melded my info. Regardless, i am interested in personal concerns/likes/dislikes regarding the RFZ concept if you feel like writing.The main issue is that it's about 30 years out of date! :) Seriously, RFZ is a much more common design today (also sometimes called "non-environment", but they aren't really the same thing). - Stuart -What are the concerns with the LEDE approach that i should be aware of?
The search function is your friend. :mrgreen: For starters, including the links in the thread: http://johnlsayers.com/phpBB2/viewtopic.php?f=1&t=14646&hilit=rfz+lede Well researched, AndreRegardless, i am interested in personal concerns/likes/dislikes regarding the RFZ concept if you feel like writing.
Thanks Andre, i have quite a bit of reading on what both designs are(mhoa,RSD Newell), what i am after from you guys is YOUR opinions as you are the ones who have the experience building/using them and because you are the people i will be asking for some help from. Surely you personally favour one or the other or some other design, why? If you had to go work for 1 year in one or the others of equal quality which would you choose and why? No contests, just why does Joe like this and Stan like that, perhaps my interests and working methods are more in line with one or the other and a consideration i hadn't thought of will arise. But in the mean time i am reading and researching myself, thanks for the links. Rod Gervais's book showed up this week, thanks Glen.The search function is your friend. :mrgreen: For starters, including the links in the thread: http://johnlsayers.com/phpBB2/viewtopic.php?f=1&t=14646&hilit=rfz+lede Well researched, AndreRegardless, i am interested in personal concerns/likes/dislikes regarding the RFZ concept if you feel like writing.
Your question is nebulous. My opinions are that, mine. The application drives it, as it does in profesional design. Strictly control rooms with RFZ. Mixing rooms with Next Generation RFZ© design. That being RFZ concepts with fully diffusive surfaces and ISD accomplished by room size. I just created Next Generation RFZ© to make it sound fancy and marketing savvy. The former provides more accuracy and the latter more ambiance. LEDE is obsolete.Thanks Andre, i have quite a bit of reading on what both designs are(mhoa,RSD Newell), what i am after from you guys is YOUR opinions as you are the ones who have the experience building/using them and because you are the people i will be asking for some help from. Surely you personally favour one or the other or some other design, why? If you had to go work for 1 year in one or the others of equal quality which would you choose and why? No contests, just why does Joe like this and Stan like that, perhaps my interests and working methods are more in line with one or the other and a consideration i hadn't thought of will arise. .
You are welcome. AndreBut in the mean time i am reading and researching myself, thanks for the links.