John Sayers' Recording Studio Design Forum Archive

ISO/Vocals booth ...

This is the entrance to the vocals booth

this is the control room ...

inside iso/vocals booth ...

Lookin' good - how did you seal those two electrical boxes in the same cavity? Steve

Steve, one of those boxes is electrical outlet, the other one is the conduit for mic/instrument cables that goes to the control room. The two conduits run non-parallel to each other.

I sealed the edges with caulk, the contractor then filled it with joint compond and drywall tape. I also put caulk on all the small holes that were inside the boxes.

Wasn't worried about parallel runs, more that both boxes are in the same stud cavity and serving separate rooms; what you did should be OK, but ideally any boxes should be in separate cavities, or at least completely mudded on the outer walls of the box with fire-preventative "putty packs" - these do a lot to deaden any sound leakage.

This isn't necessary when boxes are in adjacent stud cavities and serve opposing rooms.

Since you're using rigid insulation, this won't be as much of a problem as if you'd opted for standard house insulation; it's just better practice to either mummify the boxes with putty or move one to the next cavity... Steve

That's a great idea, I wish I knew about it before Actually come to think of it, the electrical box is run up inside the ceiling into a junction box and the other run is connected to the second outlet in the same room.

What are these "putty packs" you mentioned?

http://www.rectorseal.com/productdata/f ... taputt.pdf

These provide double duty; they're heavy enough to be good sound deadening mass, stick where they're put, and are intumescent in the event of a fire... Steve

Looks like they sell it in caulk (tube) form also. I found it here:

http://www.bigdboltandtool.com/meta100z.html

Is it that much better than acoustic caulk? I believe acoustic caulk is also fire rated isn't it?

Not unless the specific brand claims it's fire rated - these are two entirely different materials. Acoustic caulk's main claim to fame is permanent flexibility and sealing of air gaps for sound control; fire putty is intumescent and pretty high mass, seals SORTA OK until it gets HOT, at which time it swells up as much as 10X and forms a hard char which is supposed to withstand even a fire hose.

People have used the acoustic caulk and "buttered" outlet boxes with it, but as far as I know none of the common acoustic caulks claims to be intumescent; maybe non-flammable, but it's not the same... Steve

Just a few quick questions. The pictures show some type of vapor barrier on the outside of the foundation walls. What sort of insulation was used on the foundation walls, and what kind of insulation did you use for the second set of walls and where did you get it from?

Thanks for your time.

Tim Lee

Hello Tim,

The insulation on the first wall was installed by the builder when we got the house. It looks like R19 fiber glass insulation with some type of vapor barrier on one side. It is attached directly to the concrete foundation with anchors.

The insulation on the second walls is 3" Roxul AFB. Here is the information about where I bought it from.

http://www.johnlsayers.com/phpBB2/viewtopic.php?t=2561

How is the isolation from room to room since you've built this??
Thanks for your time!!

Tim

I don't have the doors, window, and wall plates installed yet. The contractor just finished sanding the walls (he is taking a lot longer than expected). He will be starting to hang doors and window this week and then start painting. I can tell you how it is in the next two weeks.