John Sayers' Recording Studio Design Forum Archive

The more I read the more questions I have. It seems the cycle never ends...

I'm kicking around ideas for finishing my basement, 1/2 of which would become a studio (control room & tracking/Iso room) the other 1/2 would be for all purpose home use. The studio side would consist of 2 rooms, the sizes & shape are yet to be determined but, the overall space I have to work with is roughly 24' x 12' x 8'. Here's a link to the floor plan -

http://www.johnlsayers.com/phpBB2/viewtopic.php?t=2831

The space I have to work with is from the top left of the page to the 2nd support post near the stairway.

After working out the materials & costs to do it "the right way" it seems it's still a bit financially out of my reach so...

My new tentative plan is that the ceiling would be finished with 3" Roxul, RC1 (on the floor joists), and 2 layers of sheetrock. my main concern is with transmission to & from the basement to the 1st floor.

There is 9 1/2" from the top of the basement ceiling to the botom of the joist. Would 3" Roxul with an air gap of 6 1/2 inches to the RC1 & sheet rock be the most effective way of isolating the basement, or would some other approach be better?

Is it best to do 2 layers of 5/8 sheet rock? or 5/8 & 1/2?

How far apart does the RC need to be spaced? The RC runs perpendicular to the joists?

When RC1 is used on a ceiling with 2 layers of sheet rock (say both are 5/8") that would come to a total of 1 1/4" How much does the RC1 add to this measurement?

How much if any does the RC1 size vary if only 1 layer of sheetrock is used?

Would these measurements be the same if this were mounted on a wall?

Can the RC1 be mounted directly on a cinder block wall? Vertically? What spacing for the RC would be used here? I guess what I'm asking is can I use the RC sort of in lieu of studs?

If so, I suppose I'd run my AC on the exterior of the walls - in conduit? with the boxes & switches mounted on the wall with putty?

Then according to my tentative plan, the exterior walls would be cinder block, paint, RC1 & 5/8" sheet rock. The interior walls (2) would be metal studs, sheet rock 5/8" on 1 side 1/2" on the other & 3" roxul. Leaving the floor as concrete and using a drum riser when needed. I would then use 703 etc in the rooms.

Does this sound like a plan that will get me better results than recording in the 2 attic bedrooms I had been using before? Or do you think if I build in this manner I'll be dissapointed?

Thanks for any of your input!

Tom

Tom,

I'm not an expert here, but try to help where I can. I hope you are successful and happy, because I'm undertaking a similar project.

RC will typically stand the drywall 1/2" off of studs or joists, so you will lose that much more ceiling height. This is independant of the number of layers of drywall mounted to it or whether you mount it on a wall or a ceiling. When overloaded the RC can sag further, but hopefully you won't overload it.

One of the lines that people here seem to advocate the RC Deluxe line from Dietrich.

http://www.dietrichmetalframing.com/pro ... _12,46.pdf

Maybe someone else should answer this, but I don't think you really need to use special putty for surface mounting the electrical conduits and boxes. This is more of a concern if the boxes are recessed in the wall. Then you would have a transmission path around the edges of the boxes and through the box penetrations. I would think that you could just try surface mounting the electrical with standard fastening methods, and address rattles later if you have them.

Also, you may want to check out the image at the bottom of this page:
http://www.saecollege.de/reference_mate ... /Walls.htm

Adding additional drywall layers under the 1st floor subfloor between the joists you see in the basement can further improve your isolation. However, you need to make sure your joist sizes, spans, and spacing can accommodate the load of all the added drywall.

Best of luck

Tom, Philo got you started but missed a few - I'll take them in order -

There is 9 1/2" from the top of the basement ceiling to the botom of the joist. Would 3" Roxul with an air gap of 6 1/2 inches to the RC1 & sheet rock be the most effective way of isolating the basement, or would some other approach be better?

You should have insulation batts in snug contact with BOTH upper and lower ceiling surfaces for best isolation - this damps each panel to minimise any ringing, and further disperses sound within the barrier.

Is it best to do 2 layers of 5/8 sheet rock? or 5/8 & 1/2?

If you're only doing two layers, I'd stay with 5/8 - just a bit more mass, but it all helps...

How far apart does the RC need to be spaced? The RC runs perpendicular to the joists?

Yes, perpendicular; spacing depends on load and the spacing of the joists. For two layers of 5/8, typical is either joists=16", RC=24", or vice versa.

When RC1 is used on a ceiling with 2 layers of sheet rock (say both are 5/8") that would come to a total of 1 1/4" How much does the RC1 add to this measurement?

1/2", as Philo said.

How much if any does the RC1 size vary if only 1 layer of sheetrock is used?

By "size", if you mean "sag", then not much; probably less than 1/16" if I had to guess.

Would these measurements be the same if this were mounted on a wall?

Yes; you hang RC with the wide face upward, so the weight of the wallboard tends to pull it AWAY from the wall - again, no actual measurements to back it up but probably within 1/16" or less difference.

Can the RC1 be mounted directly on a cinder block wall? Vertically? What spacing for the RC would be used here? I guess what I'm asking is can I use the RC sort of in lieu of studs?

No, I wouldn't try that. First, as I mentioned the RC is designed to be hung so that it pulls away from the wall when loaded. Vertical won't accomplish this. Second, that's not enough air gap to do anything good, and may even damage isolation; you didn't mention whether your blocks are filled or hollow, if they're filled then an air gap won't hurt isolation. If they are hollow, the blocks by themselves ALREADY make up a 2-leaf wall system, and another air gap will cause LF isolation to worsen while improving MID range TL a little bit.

If so, I suppose I'd run my AC on the exterior of the walls - in conduit? with the boxes & switches mounted on the wall with putty?

This is a good way to run AC anyway; keeping it on the surface keeps holes in your otherwise tight construction to a minimum, and you may be able to use the conduit to help support your various absorber panels. There is actually a type of "conduit" designed just for this type mounting, that looks more finished -

http://doityourself.com/store/wallchannelwiremold.htm

I've seen this stuff in a couple of Home Depot's, you might wanna check your local one; otherwise, try an electrical supply place if they'll talk to a non-electrician.

Then according to my tentative plan, the exterior walls would be cinder block, paint, RC1 & 5/8" sheet rock. The interior walls (2) would be metal studs, sheet rock 5/8" on 1 side 1/2" on the other & 3" roxul. Leaving the floor as concrete and using a drum riser when needed. I would then use 703 etc in the rooms.

Which plan on your other thread are you looking at doing, and do you understand about 2-leaf walls vs. 3 or 4 leaf walls?

Does this sound like a plan that will get me better results than recording in the 2 attic bedrooms I had been using before? Or do you think if I build in this manner I'll be dissapointed?

As I've mentioned above, there are a few design flaws yet to be solved - if you can show us which plan you're working from, and a detail of your proposed INNER walls, I think we're almost there construction-wise... Steve