R13/AFB Insulation question & Ceiling Cloud Mounts

[RSKAudio]

Hi all,

Have tried searching for this prior to posting so apologies if I missed this somewhere.

Building a new home mix room inside a basement with a shared brick wall that connects to a neighbors unfinished basement/boiler room. Expanded: The current plan is to use RC along the shared wall with two layers of 5/8" gypsum (contractor's also added greenglue between the layers in the current plan), isolate the ceiling with a106r clips and channel with AFB 3" above head. Then a set of interior (mostly) soft fronted walls framed out with 4" OC703 & an additional 1/2" fiberglass board for the fabric installation. The rear and side walls of the space aren't connected to any other buildings and Summer bookings are causing this to be a multi-step thing. Aiming to get the main structure set and then work on the rear wall as time permits.

The ceiling should be just over 7' after the new layout is installed, most of the sound seemed to be traveling up into the house and then across rather than through the basement.

Electrical will be two 20 amp circuits, one with the lights and the other just outlets on the finished side. Ordered two track lights for the sides and there are three lights built into the cloud so the third pictured one in the back is probably redundant.

The original plan was to remove the drywall from the shared wall, add 3" AFB with resilient channel and two layers of 5/8" drywall and then build the treated area inside of that (the shared wall is the vertical one on the left of the drawing). After opening up some of the drywall there's R13 inside of it currently (not sure in the ceiling yet) and the contractor has suggested leaving it and adding the AFB on top of it to add to the total insulation there. It doesn't seem R13 really has much of a NRC so my question is, am I better off with the AFB and an airgap or trying to compress the R13 underneath?

My other question has to do with mounting a ceiling cloud. Picked up one second hand that has 6 moounts built into the frame with 1/4" 20 rods that were screwed into the previous ceiling. We're currently planning to hang it from the joists and add acoustic caulk to the rood passthroughs in the ceiling drywall but I'm wondering if there are any iso mounts I shouold be looking at to attach the rods to the joists or if screw in threaded mounts are fine.

Thanks so much!

[gullfo]

not sure what the isolation plan is. sound is 3D. just enhancing the one wall will only do so much, whereas the rest of the space will now become the source of structural transmission into that party wall. via the the staircase, bathroom etc. and sound exiting the window will wrap around into any neighboring windows.

[RSKAudio]

Updated with more information about the questions

[gullfo]

what options for eliminating the RC on the walls and maybe going with 2x3 metal or wood framing - set 1" off the wall?

the RC tends to be a hit or miss thing in terms of assembly and actual effectiveness. since the walls aren't load bearing, as the ceiling is suspended off the clips and hat channel, you can reduce the depth of the walls and increase the gap from the frame to the existing walls.

the AFB should be fine and compressing the R13 is also ok. too dense of a product in the walls can be just more money for no more effectiveness. save any 703/denser stuff for in the room treatment.

on the cloud, not sure how much it weighs but if you poke holes and put in solid rods into your space, they will transfer sound from/to the structure into/out-of your room. one option is use a layer of 1/2" plywood or OSB on the channel then the drywall on that. this will help for securing the drywall and should provide a good anchor for the cloud.

[RSKAudio]

Thanks a lot for your time!

what options for eliminating the RC on the walls and maybe going with 2x3 metal or wood framing - set 1" off the wall?

This could be possible but I believe the contractor has already ordered the RC so I'm hoping that will work out and end up installed properly. Any tips for checking that other than screw size and measuring?

the AFB should be fine and compressing the R13 is also ok.

Great! Feels better than throwing it out if there's not going to be a negative impact.

on the cloud, not sure how much it weighs b

I've been a bit worried about this part. It's approximately 220 pounds (I haven't been able to get an exact weight of the insulated sections due to their size). It measures 87 x 80 x 7 inches, there's about 4" of dense yellow insulation with a pegboard backing that the insulation is screwed into and wrapped up in fabric. The frame is 2x4's with a 1x7 edge all the way around. If I don't mount the 1x7's back and just wrap around the 2x4's it'll take 42 pounds off and would let me get it closer to the ceiling but I had been planning on rebuilding it as it was (hand me down from Thompson Street studios in NYC). Looking into the OSB weight loads now, the current ceiling plan was two layers of 5/8" gypsum x, would you recommend swapping in the OSB over just that section or as an entire layer?

Will definitely be in touch about the rear of the room once I get settled in.

[gullfo]

a mechanic stethoscope and a rubber mallet - someone listening on the exterior wall and someone tapping on the interior wall will tell you how much isolation has been achieved.