Topic: Dead-icated home theater room.

[ts]

Well, I recently built a new one story home and my basement is so fricking big, I decided that a "home theater only" room might be a good idea. Won't happen for a few months, but I figured I should start thinking about it now.
I have one area of the basement in mind, that is approx. 12 ft. wide by 25 ft. long and 8 1/2 ft. ceiling height and it can be partitioned off. My initial thought's are on the size of the room. Maybe too narrow? Second is, since this is from scratch, do I build it the way the rest of the basement will be built, ie: stud out the walls, insulate and sheetrock. Or could some special insulation behind the rock be used or just use acoustical panels in the room. There are other larger areas in the basement, but this one could be neatly sectioned off. Foundation is poured concrete.
One negative to this location is that it is directly under the master bedroom, but maybe some beefed up insulation could be added to the ceiling. Which leads me to my last decision. I may opt out of the sheetrock ceiling if there is some good (and nice looking) acoustical ceiling products. My neighbor is a custom home builder(not my builder )and he has ideas, but I thought I'd run it thru here first, since he is not nearly as enthusiastic as we are about our music. And his home theater room sucks.

Thanks, ts

PS: I have read articles on building these rooms, but they seem to be directed at folks who have a ton more disposable income than I do.

[spyder9]

Hey TS,

Your room is the same size as mine.  An I-beam separates the room from the rest of my basement.  I remodeled my basement a few years ago.  I went with studs, insulation (paper facing in), and sheetrock.  Acoustics are outstanding.  From the main floor doorway, my basement sounds like one large speaker.  As for the master bedroom sitch, look into some sound-deafening material, like they use in clubs.  I'd put that in your ceiling.  You then can decide whether to go with a drop-in or sheetrock for that.

Also, I am assuming you did top takeoffs for your duct work.  If so, take some space back past the I-beam so you can put in your Audio/Video system.  It will help for your limited width of 12 feet.

I can email you some pictures of my basement familyroom if you would like.  I did the work myself, with some very limited help from some friends.   Hangin sheetrock is not a 1-man job.

[scervin]

I'll post more on the subject, but I'd go wider than 12' if you can would not exceed 22' length if so.  If you can get it up to 15' or 16' that would be best.  I'll paste some room mode calculators later.  Is the height to the bottom of the duct work or floor joist?  Will it need to be dropped any?

As far as construction, the best to keep noise out of the room above would be to de-couple it from the rest of the house.  This is the room-within-a-room technique.  If you choose not to do this I would go with standard framed walls against the concrete and any room adjacent to the theater would be staggered stud wall construction.  Use 1/2" sheetrock and double it up for more isolation.  Use flex insulated HVAC duct work if you choose to tie into current system to cut down on noise transferred through returns and vents.

scott

[spyder9]

I'll post more on the subject, but I'd go wider than 12' if you can would not exceed 22' length if so.  If you can get it up to 15' or 16' that would be best.  I'll paste some room mode calculators later.  Is the height to the bottom of the duct work or floor joist?  Will it need to be dropped any?

As far as construction, the best to keep noise out of the room above would be to de-couple it from the rest of the house.  This is the room-within-a-room technique.  If you choose not to do this I would go with standard framed walls against the concrete and any room adjacent to the theater would be staggered stud wall construction.  Use 1/2" sheetrock and double it up for more isolation.  Use flex insulated HVAC duct work if you choose to tie into current system to cut down on noise transferred through returns and vents.

scott

Nice.

[ts]

Good info guys. Scott, your'e a GC, right? Only way I can do wider than 12 ft. is to move to another spot and I'm not sure if I want to do that because of the layout of the rest of the job. Ceiling height is to bottom of duct work. Good tip on the duct work, would've never thought of that. So 12X25 may not cut it? With framing in I'll def. be under 12.
Thanks!

[Lil Kim Jong-Il]

Not only would I go for the larger room, I'd probably not put it directly under the master bedroom if there is a possibility that someone who shares that room will want to go to bed before you on most occasions.  The room I use is just over 11x23 and  it just isn't big enough for a full sized system with the speakers set out from the walls as they should be.

[scervin]

Alright got a little time now.  GC?? General contractor??  Nope, just a HT/audio nut that has done too much research on the subject.  I've got a few books and am currently trying to get a theater design/install side business going.  Anyway, do you want this to be full home theater or do you plan on doing a lot of MC audio and/or 2 channel listening.  This will dictate the room construction.  If strictly HT I would look up the Dennis Erskine designed theaters over on avsfour.com in the HT builder forum (under other items).  This includes treating the entire front wall with roll duct liner and all of the walls below ear level as well, which creates a really "dead" room.  You do not want this if you plan to listen to music.  Below I have attached a link to a program I love to use when one asks how large a room should be:

http://www.realtraps.com/modecalc.htm

You just don't want a room to be a cube or multiples of eachother.  I think the few pages in that link on acoustics are pretty beginner friendly.

You will see I was pretty close with the 22' length.  Using ratio 4 (1=1.4=1.9) gives you 8.5"x11.9'x22.6', again these are just the recommended ratios, your personal needs may require different dimensions, but I'd stay short of 24' if you can.

You are working with a ver nice height and in my dream house I'll have 10' ceiling in my basement.  I've got to deal with the standard 8'-drop = 7'.  The 8.5' will give you the opportunity to put up a large screen and have a good riser height if you choose to have more than 1 row of seating.  

It is also a good idea to think about the power requirements (# circuits).  It is stadard to run a 20A to the sub, rack (I ran 2 here), projector, and a 15A for lighting/outlets.

SC

[Jason B]

Well, I recently built a new one story home and my basement is so fricking big, I decided that a "home theater only" room might be a good idea. Won't happen for a few months, but I figured I should start thinking about it now.
I have one area of the basement in mind, that is approx. 12 ft. wide by 25 ft. long and 8 1/2 ft. ceiling height and it can be partitioned off. My initial thought's are on the size of the room. Maybe too narrow? Second is, since this is from scratch, do I build it the way the rest of the basement will be built, ie: stud out the walls, insulate and sheetrock. Or could some special insulation behind the rock be used or just use acoustical panels in the room. There are other larger areas in the basement, but this one could be neatly sectioned off. Foundation is poured concrete.
One negative to this location is that it is directly under the master bedroom, but maybe some beefed up insulation could be added to the ceiling. Which leads me to my last decision. I may opt out of the sheetrock ceiling if there is some good (and nice looking) acoustical ceiling products. My neighbor is a custom home builder(not my builder )and he has ideas, but I thought I'd run it thru here first, since he is not nearly as enthusiastic as we are about our music. And his home theater room sucks.

Thanks, ts

PS: I have read articles on building these rooms, but they seem to be directed at folks who have a ton more disposable income than I do.

If you want to PM me with specific questions about all of this, I would be more than happy to walk you through each step. I just so happen to do this for a living. There are sheetrock, insulation and many other choices for deadening the room. I can help you with equipment placement as well as help you decide on what equipment best suits your room and your needs. If you would like any info, shoot me a PM.

-Jason

[ts]

Wow! You guys are dead on and really know your shit. Thanks so much. scervin, sounds like my room size is close to OK. And Jason thanks for the offer, in time you will be hearing from me.
Tony

[Tim]

+T Scott... you are nuts

[ts]

Not only would I go for the larger room, I'd probably not put it directly under the master bedroom if there is a possibility that someone who shares that room will want to go to bed before you on most occasions.  The room I use is just over 11x23 and  it just isn't big enough for a full sized system with the speakers set out from the walls as they should be.

So our room sizes are similar. Are you saying I may not get the helicoptor flying around the room effect with the narrow width? Or more so that a smaller system will produce a good HT experience in my size room?

[Lil Kim Jong-Il]

So our room sizes are similar. Are you saying I may not get the helicoptor flying around the room effect with the narrow width? Or more so that a smaller system will produce a good HT experience in my size room?

Oh no, you can still get the surround experience in that room.

My issue with the 11x23 room is that for best 2 channel audio playback I need my speakers to be away from the wall and the speakers themselves need to be seperated a decent distance.  I've found it really difficult to get the speakers in an optimum arrangement and still have a room layout that will accomodate multiple listeners in a conversational setting.  Another issue with my room is that it has to be clear enough to walk through to other parts of the house.  If I had a room that was more like 18x30 it would be better for my needs. I'd like my speakers to be 10ft apart and I'd like to sit 12 feet from them without my back being against a wall.

I think that you should pick out furniture and determine the setting before you frame the room.  Do a layout on paper and see how much floor space you need to accomodate the sitting area and then speaker placement.  For most households, the room layout will need to allow people to sit in a conversational arrangement on occasion.  I'd want to maximixe the sound performance for as many of those seats as possible while avoiding the congested feeling of a room that prevents traffic flow. 

For example, a normal 3 seat couch is about 7ft wide.  If you put that couch across the narrow dimension of the room, you'll have just 2 feet on either side to put tables or to walk around the couch if the entrance is behind.  That's why I think a wider room is a better option.  If you expect to have guests, the extra room for traffic will mean a lot.  You'll need side clearence for the surround speakers and if you install half rounds along the walls, those will also compress the available floor space. 

No doubt you could be very satisfied with an 11x23 room.  But if there is an opportunity to build out a larger space, I'd do it because you aren't going to move those walls once they are painted.

[ts]

Cool. I have a separate 2 channel listening area, so it looks like my HT room will be fine. Thanks for all the additional info.
Tony