I'm about to start a project to refinish a ceiling and some walls in my "home theater" room (actually, a preexisting room where I'm only going to complete several walls and not all -- yes, I know this isn't ideal, but this is a test case for my next home). I am going to use isolation clips (RSIC) plus two layers of drywall (DD), and green glue (GG) for the ceiling and a few walls.

My questions:

1) For sconce boxes, where do you get boxes suitable for the two layers of drywall and RSIC and yet still able to mount to a stud? Do I need to add some type of furring strip? (And even if I do, 1+ inches of drywall seems to need a deep box.)

2) I'll need to hang a projector, pulldown screen, and probably a center channel from the ceiling, which will have the RSIC, DD, and GG. Should I plan on putting in some 2x4s on some isolation mounts, in order to mount this equipment? Or can two layers of drywall handle this weight?

3) It seems as if two layers of 5/8 inch drywall is a lot of weight compared to the single layer I have now. How do I know I'm not going to cause future sagging of the ceiling?

4) How do I convince my wife to use sconces and not canned lighting? She wants the room to maintain its multipurpose flavor, so she wants enough light for reading or allowing our toddler to play. This room will also be for listening to music and has a fireplace on one side. I'd prefer sconces only, but these might not give off enough light for a multipurpose room. Can sconces give enough light? If not, what about a combination of the two -- sconces and canned lighting -- so that I can minimixe ceiling penetrations and the isolation boxes I'd have to create.

Thanks for the help.

One approach is to put the canned lights into soffets or backer boxes. It can be done so to minimize sound leakage.

You definitely do not want to add clips and channel to an existing drywall surface. The small trapped air cavity will wreak havoc at certain frequencies.

You might have a look at this article for ceiling options:

http://www.soundproofingcompany.com/index.php?/solutions/neighbor_noise/neighbor_noise_ceilings

After you make a decision on the ceiling, you can look at mounts, etc.

How about ... install a coffered ceiling and install 3" to 4" diameter halogen remodel fixtures in the coffers. No drywall penetration...wife is happy.

Here is how I was going to do mine. I think it will be ok.

There are 2 diagrams

1. looking straight up from floor to ceiling
2. If you were looking level with the ceiling

I mount 5/8 plywood to the Hat Channel, then sandwich 2x4's over the top of the hat channel and the 5/8 plywood. The 2x4's do not touch anything except the hat channel but will add some support and I can bolt the projector through the plywood into the 2 x 4's.

My projector is not that heavy but it makes me feel better.

Then with the first layer of 5/8 drywall it matches up, then the 2nd layer covers the whole thing.

any thoughts?



http://home.mchsi.com/~fun_pictures/Ceiling_Mount.JPG

I attached a 2 x 12 to 4 RSIC-DC04 clips, which in turn were attached directly to the ceiling joists. The 2 x 12 is hidden behind the drywall so it cannot be seen and is decoupled to prevent any flanking paths. It's more than enough to hold the projector mount, but the one disadvantage is you need pretty much have your projector location determined before you drywall.

Kermie, what a great image... Thanks for that.

If we assume the first layer of drywall is 5/8", then replace the drywall in the projector area with 5/8" plywood, as Kermie drew so artfully. I would simply make the 5/8" ply layer bigger, so it spans 3 rows of hat track. No need for the additional lumber.

Then top off the whole deal with a second layer of 5/8" drywall.

You definitely do not want to add clips and channel to an existing drywall surface. The small trapped air cavity will wreak havoc at certain frequencies.

You might have a look at this article for ceiling options:

http://www.soundproofingcompany.com/index.php?/solutions/neighbor_noise/neighbor_noise_ceilings

After you make a decision on the ceiling, you can look at mounts, etc.

Ted,

It was always my intention to take down the ceiling and add RSIC, DD, etc. This is the lower room of a raised ranch, and the fuse box is in this room. In order for me to run any power cables, projector cables, speaker wire, etc., I really need to take down the ceiling.

I think the other ideas (boxes for canned lighting, 5/8 inch plywood or isolated wood) are great. I think the coffered ceiling would be fantastic, but this room has a metal beam (in a drywall box) that spans the room and penetrates some 7 or so inches into the room. I'm not sure the coffered ceiling would work well with this system (not to mention that I was going to mount the project right near the beam, and this would penetrate the coffered part of the ceiling).



A few more questions:

1) I know the beam is going to present some acoustical and isolation problems, and I'm not sure how to fix those. Any ideas? Can I simply DD and GG? (This room is simply a test room so that I test out some isolation techniques prior to buying a different house one day and creating a true HT room, so any suggestions are appreciated.)

2) How does one add molding (crown or baseboard) in a room with RSIC, DD, and GG? Typically, the molding would be nailed into studs, but to do so would lessen the effectiveness of sound isolation. Is it possible to nail into hat channel? Or can one glue the molding?

Thank you.

The beam would be isolated with a clip soffit system. Decouple from the beam itself and insert mass, absorption and damping. The crown molding would attach to the hat track as you said

Kermie, what a great image... Thanks for that.

If we assume the first layer of drywall is 5/8", then replace the drywall in the projector area with 5/8" plywood, as Kermie drew so artfully. I would simply make the 5/8" ply layer bigger, so it spans 3 rows of hat track. No need for the additional lumber.

Then top off the whole deal with a second layer of 5/8" drywall.

I actually tried this and found it pretty difficult to get the plywood to screw tight the hat channel, and not pull the screws out. I'm not sure what I was doing wrong, but I eventually abandoned this approach and used some 2x12 blocking attached to RSIC-DC4s.

The hat track is easier to strip out than wood. Pre-drilling and Counter sinking the screw head in the plywood would help.

Any answer re deep electrical boxes or other techniques for adding boxes to walls with RSIC + DD. Where do I find such boxes or techniques?

Thank you.

The hat track is easier to strip out than wood. Pre-drilling and Counter sinking the screw head in the plywood would help.

Thanks, again, for these suggestions.

Any answer re deep electrical boxes or other techniques for adding boxes to walls with RSIC + DD. Where do I find such boxes or techniques?

Thank you.

I took a look at this thread (after modifying my search terms to be able to find the thread):

http://www.avsforum.com/avs-vb/showthread.php?t=1078212&highlight=dd+mount+box

I think I'll just use old work boxes, fire putty them, and acoustic caulk around them. I'll do this for both high voltage and low voltage boxes.