Hello all,
To start let me just say, I've learned a lot from these forums! So thank you to everyone who contributes. Over the last 5 months I have been designing the following multi-room, double wall, room-within-room architecture, home recording studio. http://www.johnlsayers.com/phpBB2/viewtopic.php?t=16598
Some of my final CONSTRUCTION questions before I start are:
- I read somewhere that "you cannot decouple twice". Is Resilient Channel necessary if you already have a decoupled double walls everywhere? green glue?
- Are 2x6's (16" O.C.) ok for a 16 foot span if they hold: 5/8" drywall (and typical HVAC, lighting, electrical)
- Are 2x4's (16" O.C.) ok for a 14 foot span if they hold: 5/8" drywall + green glue + 5/8" drywall sandwich (and typical HVAC, lighting, electrical)
Neither rooms have any live load on them (or deadload from living space).
- Any comments on using 3" PVC in the walls for audio cable buses?
- For insulation I was looking at: Johns Manville 384"L x 15"W x 3.5"D R-13 Fiberglass Insulation Rolls. Kraft Faced vs ComfortTherm Plastic Faced (33% more expensive)... any preference?
Thanks in advance for any comments or feedback!
Final questions before I start building, please feedback.
Originally posted at johnlsayers.com, topic 16599.
Well you CAN if you want to... it just won't do anything! That would be like taking a shower while in the swimming pool: it wont make you any wetter! If you are decoupled, then you are decoupled. Doing it again wont accomplish anything extra.I read somewhere that "you cannot decouple twice".
Not necessary: A waste of time and money.Is Resilient Channel necessary if you already have a decoupled double walls everywhere?
Does not decouple: It is constrained layer damping, a very different principle. Yes, it is very useful and worthwhile, if you can afford it and if you need it. - Stuart -green glue?
"- Are 2x6's (16" O.C.) ok for a 16 foot span if they hold a: 5/8" drywall + green glue + 5/8" drywall sandwich (w/ NO weight from above)?
- Are 2x4's (16" O.C.) ok for a 14 foot span if they hold a: 5/8" drywall + green glue + 5/8" drywall sandwich (w/ NO weight from above)?"
No and heck No.:)
When you say span, is that from outside of the framed wall to outside of the opposite framed wall? If you said yes, then the above answers do not change.
If you said no, meaning that it was from inside of framed wall to inside of the opposite side framed wall, then the above answers do not change, and you need to get someone local to help you in this determination.
You assume there is no load above or on these joists. I would beg to differ...why do people say that, beg to differ :) Reason why I would bring this up is that you have insulation...you have the weight of the wood, the weight of the sheathing, the weight of the CLD product, you have HVAC, you have silencers, you have wiring...etc., etc.
2X6 with a 5 pound dead load, that is all the things I mentioned above, is expected to span 17' 8"...but is rated for a 5 psf dead load under these conditions. Your conditions match or exceed this limit...thus...no :)
On the best of days 2X4 #2, will not make this span even if it is rated @ 5 psf dead load.
So you need to talk to a real fella on your side of the screen, and ask him or her if you should bump both materials up to 2X8 and 2X6 respectively.
When I said there was no load above the joists, I didn't mean literally no added weight. I'm novice with ceiling joist code and lingo, but what I think I'm trying to communicate is:
- there are no live loads on the joists.
- there are no added dead loads on/above the joists from living spaces.
My first span of 16' will only be 5/8th DW and R13 (and your typical HVAC, lighting, and electrical). Sorry, I initally mistakenly said this was a drywall sandwich surface but it's not. (Not a recording studio room)
- Will 2x6's 16-OC suffice now?
My second span of 14' (is a recording studio room, and) will hold: 5/8" DW, Green Glue, 5/8" DW, R13 (and your typical HVAC, lighting, and electrical).
- Should I use 2x6's 16-OC, and then double them up instead?
The ceiling heights thruout the three studio rooms will be beweet 7 and 8 feet, so height is at a premium and trying to be maximized.
Does anyone use any kind of in-wall bus for the audio cables? So in case you need to pull another cable in the future. I was thinking of using like 3" PVC. Becuase the studio is rooms-within-rooms, I won't have to drill 3" into the 2x4 studs; I can go around the framing top plate...
Here's the thing...the information I gave you came directly from the Industries suggested spans with the lumber in question.
Nothing has changed...the material you are wanting to make this span with is NOT rated to make that span...
And doubling the material up does not make it stronger. It pushes the cost up and adds more weight to the already over-spanned material.
It COULD be that reducing the layout to 12 inch centers would help you gain more length, but in the real world, the lumber needs to be bumped up to the next larger available size...all things being equal with the current unknown variables that surely exist in this build proposal.
Thank you. I will bump up the ceiling joists in both rooms to 2x8's. The builder in the lumber dept. at Home Depot pretty much reinforced what you said too.
Considering what else you might want to hang from them in the future, you might even want to take that to 2x10... When it comes to really heavy things hanging over my head, I'm all for overkill, and extra safety margins, even if it costs a few dollars more....
- Stuart -
As far as hanging stuff, I'll probably just too some somewhat light track lighting. Because I only have 7' to 8' of vertical space to work with (basement studio), I need to maximize the ceiling height. So if sufficient, I will stick with the 2x8's.
So no one has done anything special with cable bussing? Have you guys just run the cables straight thru the walls behind the drywall and not in any kind of piping material?
What does your local building code say? Personally, I run ALL cables through PVC conduit, decoupled part way as necessary. But your local building code might have some rules on that. - Stuart -So no one has done anything special with cable bussing? Have you guys just run the cables straight thru the walls behind the drywall and not in any kind of piping material
3 inch PVC? Decoupled with a... short, maybe 6", rubber coupler of some sort?Personally, I run ALL cables through PVC conduit, decoupled part way as necessary.
just reading thru on your build thread ...
As a point of note ... regarding 'hangings' from off the ceiling ..
I'm getting ready to hang ceiling clouds. These thing weight in at ~ 70lbs each. There
will be at least 3 of these ... so around 210+ lbs
Two different things RJ...you are talking about clouds...with an inflated weight depending on the room, and the other is conduit in general for moving cables in and out of the rooms.just reading thru on your build thread ... As a point of note ... regarding 'hangings' from off the ceiling .. I'm getting ready to hang ceiling clouds. These thing weight in at ~ 70lbs each. There will be at least 3 of these ... so around 210+ lbs