Building It!

[apostolakisl]

After a lot of research and cost/benefit analysis/guessing, I have started on my theatre.

I am buidling it in an attic space above the master bedroom. Sound control is important so a lot of effort has gone into that. After moving an HVAC unit, some plumbing, some electrical, a central vac line, a ceiling speaker (bedroom below), and roof bracing, I was able to get a 13 by 18 space with some sloping ceiling on the one side.

I have so far put in the floor. The floor is floating 2x12's spaced in between the ceiling joists resting on the walls of the room below. I would have prefered trusses for the floor but the extra width was going to be very challenging becuase of ceiling fixtures in the room below. I used blocks of sylomer as the floating medium. Supposedly this is going to keep vibrations of the room structure from conducting into the rest of the house. The floor is not touching the house in any way nor is it screwed, nailed or otherwise connected, except for where it rests on the sylomer which is glued to the bottom of the 2x12's where it rests on the top plates of the room below. I put a 1.125 inch tongue/groove subfloor on that which is glued and nailed. I also put 3.5 inch thick mineral wool insulation under the subfloor.

That took me and a buddy about 30 hours to do! It is such a pleasure to not have to hop and trip anymore on the flimsy 2x8's ceiling joists that used to be there. After all of that we only popped 3 nails on the ceiling below.

Next step is to build the walls and ceiling which will be attached only to the floor and thus will float as well. Again I will use the rock wool in the walls and am putting the quiet rock 525 up. I am going to surface mount the lighting and other electrical to avoid holes in the quietrock. I thick carpet padding and carpet will go on the floor and an exterior grade door will be used to the room.

I will report the results when I am done. Probably will be another 8 weeks or so.

 

[Neurorad]

That's awesome. Is the Quiet Rock 525 in the form of rigid boards? Have you considered double drywall? Will be hard to do surface mount electrical, line voltage and low voltage.

Enough room for a rack? Projector? Any windows to worry about?

AVS HT thread?

 

[apostolakisl]

Quiet rock 525 is 5/8 thick and, to the naked eye, looks like two thin pieces of drywall laminated together with a rubbery like glue. According to them it is worth like 10 sheets of regular drywall stacked together. They have several other products to pick from with the thickest being over an inch. The stuff ain't cheap at $50/sheat for the 525 and the thicker stuff I think is like $200. The thick stuff is supposedely what movie theatres use between the theatres.

No windows, it's an attic with the spray foam on the ceiling so its all sealed up and inside the insulated shell. I have been playing around with a temporary screen and various positions of the projector on a temp stand trying to figure out the best final configuration.

I am going to do minimal electrical since not much should be needed. I will build enclosures for the projector and AV equipment after the shell of the room is done keeping all of that inside the sound insulated space. The big "hole" will be the HVAC ducts but will hook them to a unit that doesn't serve a sound sensitive part of the house. I am thinking of crown molding with indirect lighting hidden in the crown which will hide all of that. A couple of outlets on the back wall and a power strip in the AV closet should suffice. If I elevate the back row of seats that will be an easy place to hide wires. I will watch a few football games and movies in there with different arrangement before I build it out just see what is most comfortable. Now that I have the platform life is easy and other than the sound escaping to the rest of the house and the fact that it is raw wood everywhere, it is great viewing already! I will be watching my team in there Saturday unfinished and all.

I will surface mount the thin style boxes for plugs/switches but still put the wires in the wall. I can drill a small hole just big enought for the wire immediately behind the box and then caulk the wire where it comes thruogh with sound insulating caulk.

 

[electron]

Sounds pretty interesting! Time to start a CT blog so we can easily follow your progress B)

 

[AnthonyZ]

Just thought that I would share my experience with the Quiet Rock. We had a client that insisted on using it in his theater several years ago. Paid a $hit ton of money for it. It was a pain in the you know what to work with. The sheet rock contractor hated working with it and the end results were less than marginal. From my perspective, there was no discernible difference in sound migration whatsoever. Much like a Bose owner, the client had a vested interest in it's performance and was convinced that it was great. No one else who worked on the project (who hadn't had to shell out the dough for it) agreed. We all thought it was a waste of time and money.

 

[Neurorad]

Lou, seems like you need to do more research on the QuietRock, to make sure it's what will serve your needs well.

http://www.avsforum.com/avs-vb/search.php?searchid=16057440

Make sure you use conduit to the projector.

 

[apostolakisl]

I have done a lot of reading. It is very easy to sabotage yourself doing these sound attentuation projects. Cutting holes for just about anything, even small ones, can neutralize all kinds of painstaking work. This is why I am not even going to try to try and put in recessed gang boxes or canned lights. Floating the room with no attachments to the rest of the house will be a big help as well. I know for sure that if I hired this out, there is no way that the temptation to brace something to the rest of the house would not be contemplated by the work crew and probably done. Doing it 100% myself keeps this out of the question. My buddy who is helping me has even tried to cheat! He keeps suggesting it and I am just about to fire him (he is working for beer). B)

I have already played with the 525 and it isn't much harder to work with than regular drywall. A little heavier and you have to score it deeper or cut it. The thick stuff would be a different story all together and I would never even consider it. The weight alone would be a killer. As compared to regular drywall, this is going to add about $1000 to the cost of the room. In the grand scheme, this is acceptable risk.

In real life, it is really hard to compare these things. It isn't like you are going to build the room one way, tear it out and build it another way just to see which was better. These things are proven in labs, but in the field it is hard to duplicate the lab environment. I will do my best.

This much I can tell you. Before putting any soundproofing in, you can talk in a nomral voice and easily hear it in the bedroom below. I also know that no matter how hard I try, some sound will get through in the end. About the only thing that really really kills sound is sand filled walls and I simply can't put that on the second floor.

 

[apostolakisl]

Well this theater building thing is a serious amount of work.

I now have the floating floorjoist/floor system, the walls and ceiling built off of it. The ceiling was a serious piece of engineering. There are three roof lines comming together and I didn't want to give up any ceiling height and couldn't use the roof rafters to support my ceiling at all. I built a very elaborate set of trusses to do the job. The angles, oh the angles. . .so many angles. This ceiling is going to have more facets than a diamond ring.

Anyway, i put sound deadening exterior sheathing on the exterior surface of the walls and have packed the spaces with rock wool insulation. I have started to hang my quietrock 525. This quietrock is dense stuff. It is a two layer sandwih, one layer has the consistency of hardyboard and the finish layer is like a superdense gypsum. You can not score and snap (they claim it can be done but recommend cutting it. . .I agree). I am having to cut this with the table saw. The good news is this is making for very accurate and tight seams. At $55/sheet I am measuring twice cutting once, you can't stretch it.

I am feeling good about things. Even without the drywall in place I sent my wife into the room and I went to the master bedroom immediately below it. Talking in a normal volume voice could not be heard at all. Screaming at the top of her lungs was audible but very muffled. The walls of this room are against open attic space that is above the bedroom so through the floor is not the only path.

I had hoped to be done for the bowl games. My kids (5 and 7) told me how well I was doing and that it for sure will be ready for Chrismtas next year. They may have more insight than I give them credit for.

Anyway, if screaming is barely audible without any drywall, I expect this to be a success.

 

[Neurorad]

Wow, that's awesome! Even without the Quietrock?! That effort on the floor really paid off.

 

[tmbrown97]

Anyway, if screaming is barely audible without any drywall, I expect this to be a success.

If nothing else, you have a place to go vent!

one consideration - instead of an exterior door, have you looked at interior "quiet" solid-core doors? Exterior just means it'll hold up to the weather - but those quiet doors work pretty well... I put them on the master and nursery in my last house and could barely hear the crying baby

.

I also must say that because you're doing this yourself, as long as you have good attention to detail, you'll probably have much better results. I had a contractor do my last place - and even though the contractor "got it", he wasn't on-site when his "crew" was hanging the drywall - so when doubling up sheetrock, they didn't stagger direction, caulk, or even cut good straight holes... so that killed a lot of my soundproofing. Lessons for next time. Unless they specialize in the field, they'll take shortcuts without having a clue.

 

[apostolakisl]

If nothing else, you have a place to go vent!

I also must say that because you're doing this yourself, as long as you have good attention to detail, you'll probably have much better results. I had a contractor do my last place - and even though the contractor "got it", he wasn't on-site when his "crew" was hanging the drywall - so when doubling up sheetrock, they didn't stagger direction, caulk, or even cut good straight holes... so that killed a lot of my soundproofing. Lessons for next time. Unless they specialize in the field, they'll take shortcuts without having a clue.

So true. I have more than once considered going to the HD and hiring day laborers to come over and whip it out in a few hours. Each time I consider how hard it would be to be to get them to slow down and do it right and just keep trudging away myself.

The door of the room opens to the game room so if it leaks a little sound it won't be a problem. If it leaks too much I will look into one of those quiet doors. The current door is a solid core door with weather stripping and was already there, I just had to unhang it from the house wall and hang it on the theater wall. Still haven't figured out how I am going to deal with the trim work where the gap is yet.

 

[apostolakisl]

Finally (almost) the room is done (pretty much). Just in time for the super bowl. I forced the situation by scheduling the carpet installation for yesterday, so I had no choice. I was up until 2am Wed and Thurs painting and doing the trim work.

Anyway, I am very happy with the results. The screen is 100 inch ScreenGoo painted on (just put the last coat on an hour ago). It works very well and is supposed to get better as it cures.

The sound insulation of course has been the biggest part of this build out. I could have done it for at least $3k cheaper and have been done 2 months sooner had I skipped that step. Anyway, it appears that it did work. The master bedroom is directly below the theater so I wanted this to work. With the volume turned up to the loudest that I would ever want (and I do kind of like it a little loud, loud enough that my wife insists I turn it down), you absolutely hear nothing in the bedroom. Turning it up to teenager volume you hear muffled sounds. And I still have some holes that I haven't put the sound caulk into. I haven't hooked the subwoofer up yet, my bet is that soundproofing won't work that well with 20hz sounds.

Now, let me tell you about the sound caulk. If I never see or touch that stuff again, it will be too soon. I used the quietseal brand and it is absolutely awful to work with. Imagine the stickiest, stringiest, gooiest, must awful chewing gum that you ever stepped in. . . now multiply that times 10. I put it around the sheets of quietrock and filled holes with it. When you press the sheets of quietrock together extra squirts out and it has to be removed. Also, when you accidentally touch the edge of a sheet to the face of another (rocking the corners) and smear it all over, that need to be cleaned. I went through a lot of acetone. I did discover that Gojo (the automotive hand cleaner) takes it off of skin really well, but you can't use that on sheetrock.

I have more sound equipment on order, a popcorn machine is coming any day now, and the wall sconces are on their way. Also, the door on the other side isn't trimmed out and I need to trim out the screen.

I bought 6 of the palliser rhumba power recliners (2 rows of 3) with the back row elevated 10 inches. I am very happy with them so far (that includes using them last night and today). They are very comfortable and hold you in an ideal position for viewing.

I'll attach some photos when I get the final details installed.

 

[Neurorad]

Wow, what a great feeling! Congratulations! Glad the effort on the soundproofing paid off.

But really, I got to the end of that post, and no photos?! :lol: