Framing in a dedicated media room - looking for advice

[drman]

Hi everyone. I'm just finishing framing a 14.5' x 21' dedicated media room - theater and audio. Here is the setup:

******** EDIT *********** It doesn't look like my attempt at drawing is going to work. Hopefully my explanation will make sense. I have a standard 7.1 speaker setup, but don't know where to place the second sub for 7.2.

________________21'______________________
| sub spkr |
| |
| spkr ****** spkr |
|-- * * |
| | 52" LCD Seating * | 14.5'
| | later a screen * * |
|-- ****** |
| spkr spkr |
| |
|_____ _________spkr ______________|
pocket
door

I'm planning on a 7.2 configuration and I'm not sure about the placement for the second sub.

This is a basement, and the exterior walls have pink insulation between the 16" on center studs. One 21' x 9' section of the room is 8' ceiling, and there is a very large sofit of 6' 10" ceiling on the remaining 21' x 5.5'.

I'm planning to drywall the walls, maintaining the insulation on the interior walls. I was planning on 3/4" drywall.

On the ceiling I am planning on 1/2" drywall on the 8' section and and 1/4" drywall on the 6' 10" section to maximize ceiling height and minimize the possibility of sagging soffits that made from 2x4s spanning up to 48" of duct work.

I am considering batt insulation in the ceiling, and I would have room over the duct work to maintain that throughout. I don't know if that does anything for me acoustically, but it would improve noise reduction.

Here are some questions:

1) Is 3/4" drywall a good option for the walls? I have thought about making some acoustical panels, if needed.

2) Is drywall a good option for the ceiling, acoustically? I think the soffit is going to do some funky things to the acoustics of the room, but I don't know if there's a way to minimize that.

3) Where should I run wire for the second sub?

4) Is there a significant acoustical advantage to a suspended ceiling vs. drywall? I prefer the looks of drywall, but I'm willing to bend on that if panels are much better acoustically.

I'm planning to run 3 circuits. One 15 amp for center lights, sconces, and non-AV outlets. One 15 amp circuit for AV components, TV, and future projector. One 15 amp for both subs.

I would appreciate and welcome any suggestions and advice.

Thanks!

 

[drman]

A couple of photos

Here are a couple of photos of the basement in its current state. This is very similar to a basement discussed here last month, and the suggestion was made that the ducts be split to either side of the wall. I loved that suggestion, but it's not going to work in my case. The heating duct is the inside duct and it would be too costly to have it moved and it's not something I feel competent to do myself.

I had planned to center everything in the room, but I'm now wondering if it would make more sense to push the seating/viewing off to the side. This would allow me to put up a screen that is roughly 9' wide in the 8' section of ceiling.

As I said in the earlier post, the dimensions of this room are 14.5' x 21'.

 

[Alex2507]

It sounds like you might be self performing the carpentry and the electrical. Just a quick speculation about the electrical ... I don't think lights and outlets should go on the same circuit and why not go with 20 Amp circuits for the A/V and subs?

Regarding the carpentry that sofit framing looks ... funny. A 2"x2" metal L angle on the corner seems like it might help but I don't know about turning studs on their sides like that to begin with. 7/8" metal furring strips (high hat) would have been my choice and they only need to be supported every 4' so you would be good on that span.

Insulate everything you can and use 5/8" drywall everywhere. It helps with sound transmission issues. If your framing won't hold 5/8" ... start again. That sofit looks like it could go up more but 6'10" in a basement is still doing good.

Acoustical ceilings in basements drop the height about 4" from the framing to be able to squeeze a tile in and they are known to rattle. I'm against them for H/T.

You absolutely must see this one thread on like the most soogin basement H/T ever. It's a Canadian guy. He did some interesting stuff with his ceiling and sofits not to mention his wall panels. I'll see if I can find that.

Got it ...

http://forums.audioholics.com/forums/showthread.php?t=52962

 

[drman]

Thanks Alex. I am doing the framing and wiring. Good point on the 20 amp ... no reason not to do that.

Do you happen to know where I can get info on the L brackets for framing a soffit? I wonder if I could get away with the 4' span and 24" on center? I googled it, but didn't come up with anything useful. I actually used steel studs on some of the walls, but I didn't feel like they would be as sturdy as 2x4s over a 4' span. I couldn't find any specs one way or the other, I suppose because there are too many variables when talking about grades of wood and guages of steel.

How would I tag the drywall into an L bracket, as the lower piece of the L would have to be would be perpindicular to the duct? I turned the 2x4s on their side to maximize clearance, but I'm not happy with the result and I still wonder if it's going to sag. I've been able to run a small cable between the ducts with a tension fastener to give support in the middle, but I can only rig that up on a few of the ribs as working space is restricted by other ducts and returns inside the joists above the large ducts.

That theater setup you posted is incredible!

 

[Alex2507]

That 2x2 20 Gauge L-Angle is 10' long and would make a continuous corner where your sofit turns up. You could also place one at the wall with a leg turned down and then put a 4' length of high hat in between the 2x4 studs. 24" on center on a ceiling is too far apart.

A 2x4 on it's side is 1-1/2" and will sag eventually I believe but high hat/metal furring is only 7/8" and won't sag. By code it gets supported every 4'. Honestly you should tear that down or at least add the metal framing. Any drywall supplier will carry 20 gauge angle and high hat.

How would I tag the drywall into an L bracket, as the lower piece of the L would have to be would be perpindicular to the duct?

You're clearly not getting this and it's not that it's complicated but I don't think I can get the idea across in type. Another thing I wonder about is if you crowned the 2x4's. This is kind of a show and tell game. I think a Craigslist add asking for a metal framer for half a day would get you that sofit built properly with the least amount of hassle. I think you can add metal to it and they have 1-1/2"x1-1/2" angle for where your opening is and your 4' 2x4's sit on top of another 2x4.

A member named Sawzalot is much better versed in wood framing than I am and he's the guy I would want helping me correct that sofit. Are you opposed to taking that framing down and starting again? Look at it like making a bad knot while tieing your shoe laces.

I saw the metal walls. Be careful on walls where you have doors as the standard jamb is meant for wood framing and 1/2" drywall. Metal and 5/8" board grow your wall 3/8" and that's a little too much to caulk.

 

[drman]

I sent Sawzalot a message. I think I understand what you're saying now, and it makes sense. I'm also not opposed to tearing down the soffit and starting over. I'd rather get it right now than have to deal with sagging soffits down the road. Thanks again for the advice and ideas.

 

[sawzalot]

I took a look at the pics and would also consider you try again that very first 2 x 4 at the floor joist should really be on the flat 3 1/2 side, glued and screwed into the bottom of the floor joist. I think you have it up on the 1 1/2 edge so you must have toe nailed or screwed it in which over time could be a failure due to weight from rock and vibration from floor above, those edges on the 2 x tend to split easy. I also notice that the only outside corner does not have one continuous edge which is never a good thing. I always found the easiest way to make that Soffit is to lay your 2 x 4 on the flat as close to the duct work as possible fasten with glue and screws to the floor joist now I like to take a piece of 5/8 ply and rip it long ways to the width which would be the distance from floor joist to lowest point of duct work plus 2 inches this gives a half inch clearance between the 2 x 4 's on the flat, yep on the flat from the bottom of this ripped ply back to the wall, now if you want some high hat lighting in the sofft you need to rip the 5/8 ply the distance from bottom of floor joist to the lowest point of soffit plus 4 inches so you could turn the 2x4 up on edge to give you more room for the cans.
Here is a pic of what I mean I hope this gives you a better idea:

 

[sawzalot]

I know Alex has a concern with the 2x for the soffit ceiling being on the flat in regards to deflection and bowing but if you have issue with head room and clearance you would be fine with this I don't believe there would ever be and noticeable bow in this application it is done all the time, now if you were getting into a length greater than 30 plus inches it could be getting to the point of going up on edge. Just remember to give the boards a quick peek and put all slight bows upwards so as you don't give it a head start in the other direction.

If you were to save the work that is there I would consider the rip of ply over the face studs from the joist down to the outside corner of the soffit so that you can maintain a nice edge the length of the soffit it would also tie the wood assembly together, you could also rip the 5/8 about 4 inches wide and the length of those bottom flat 2x's if you wanted to prevent them from bowing down just hold the bottom edge even with the bottom of the 2x and tack them in. Don't forget to stuff this full with sound proofing insulation, don't want that hollow boom boom going on.

 

[drman]

Thanks Sawz. I will re-do it as you suggest, but I think I'll also incorporate Alex's suggestion and use 7/8 high hat metal furring strips on the bottom. You mention in your second post that the 2x on the side is okay unless you're spanning over 30 inches. I'm spanning 48 inches without support in the middle, so it sounds like I need something less likely to give. I'll also be adding insulation to the cavity.

One last question. Since this is fiberglass ductwork I assume it doesn't expand and contract like metal ducts, so is there a need to leave 1/2" clearance between the duct and my metal ribs. I would like to butt the ribs up against the duct to maximize ceiling height, unless that's likely to cause problems.

Thanks a lot for your time and suggestions.

 

[Tubamark]

Thanks Sawz. I will re-do it as you suggest, but I think I'll also incorporate Alex's suggestion and use 7/8 high hat metal furring strips on the bottom. You mention in your second post that the 2x on the side is okay unless you're spanning over 30 inches. I'm spanning 48 inches without support in the middle, so it sounds like I need something less likely to give. I'll also be adding insulation to the cavity.

One last question. Since this is fiberglass ductwork I assume it doesn't expand and contract like metal ducts, so is there a need to leave 1/2" clearance between the duct and my metal ribs. I would like to butt the ribs up against the duct to maximize ceiling height, unless that's likely to cause problems.

Thanks a lot for your time and suggestions.

I'd say you probably can get away with putting against the duct, as long as the duct is not rigidly connected to anything else. It's very important that everything is resilient - a "knock" on the soffit should go nowhere. If it could be transmitted to any part of framework (joists above, whatever), it's best to avoid touching it with your hat-channel. You can spare another 1/4", I imagine.

--Mark

 

[Alex2507]

I would like to butt the ribs up against the duct to maximize ceiling height, unless that's likely to cause problems.

Bad idea. #1 the duct wont be straight or level. #2 one thing will energize the other thing and then both things will resonate and you theater will suck.

The vertical part of the sofit ...

no, first soffit has 2 eff's.

2nd ... here's a pic. This guy is using track instead of angle which is silly.

He should only be using angle. On the ceiling (top right of pic) the L should be sticking into the room so you have a continuous piece of metal to screw your ceiling to and the ceiling drywall should go on first but don't sweat it if it can't.

Cut a sheet in half (24" strip) and jam the factory seam to the ceiling across the whole room. Screw 12"O.C.. On the back of the hanging drywall snap a line at (my guess is 14" down from the ceiling measured at both ends) whatever your lowest point is for the duct plus 1-1/2" to allow for metal and just room to work/separation/calculation errors/luck/etc.

Screw angle to that line on back of drywall. Score (cut paper with utility knife) drywall below angle. Snap drywall at cut. Score front of drywall along crease created by snap in front and you're done. Secure ends where soffit attaches to walls with more angle in plumb position.

Each end of the drop gets leveled to the wall (left in pic). Measure down 1-1/2" from there and snap line. That will be the bottom leg of the 1-1/2" angle you screw there. Your high hat can then span the left angle on the wall and the right angle that you hung down with drywall at 16" O.C.

Nothing against wood but metal ... screw that ... wood sucks. Metal is straight, cuts with tin snips, bugs don't eat it and it doesn't rot. Oh yeah, at the lower corner at the bottom right you would run a line (string) from one end to the other so you could lock the hanging part to the wall with high hat in a straight line.

I'm still all for throwing $100 at a metal framer and having him show you how.

Glen Kuras and bpape are totally invited to comment on above rec and if it were me I would sort of pick their brains for advice. Jostenmeat and BMXTRIX too.

 

[drman]

This makes sense to me. I've read that drywall can be used as the vertical material for a soffit, as you suggest, because it is very strong vertically.

I won't have the top L facing into the room because I'm going to be furring the ceiling down with 2x4s on end to clear the gas pipe and water lines, so my ceiling next to the big soffit will attach.

Everything else you said sounds like the way to go. So for now I'm going to ignore the soffit so I can get the electrical and sound wiring run before I start the drywall.

Thanks again for the help! I've been worried about how to properly span that wide span of duct work and I'm feeling very good about this solution.

And you're right, metal is so much easier to work with. I used 25 gauge on part of the basement - mostly in an area that isn't shown in my pics - and the crimping tool makes framing a breeze. It's an Erector Set for old dudes.

 

[drman]

... it's best to avoid touching it with your hat-channel. You can spare another 1/4", I imagine.

--Mark

Thanks Mark. I agree, it's just not worth the risk, and I am going to leave a gap between the duct work and my framing. I appreciate the advice!

 

[Alex2507]

and the crimping tool makes framing a breeze.

They have framing screws that you will want to use on the soffit to attach metal to metal. In 25 years I have never used that crimper and neither has anybody else that I have seen. Since you're lowering your ceiling you might look into framing systems that use 7/8" metal furring suspended on rubber.

I searched for pic's and found this thread at AVS. It has all kinds of neat info and links. To lower a ceiling the last thing I would use is 2x4's ... unless they were free. Even without the fancy rubber mounting clips I would still be looking to do that with metal ... probably 1-5/8" studs.

Good luck and keep us posted. We like pic's.

 

[sawzalot]

Well then ^^ Hmmff .
I like either approach but of course I am partial to the wood, all the girls like it
Good luck with your HT and as Alex said , please keep the pics coming.

 

[drman]

Thanks again, Alex. I'll look into 1 5/8 studs. I've got to get the gas pipe moved up close to the ceiling, but I don't think that's going to be a big deal. There's enough flex on it to push it up there, but I think I'll have the extensions on the appliances lengthened to eliminate any chance of flexing it too much.