[saisunil]

Hi

We are in the process of building a home theater / media / tv / game room.
The room has been framed but awaiting insulation and drywall. There will be a 20 amp dedicated circuit and GIK acoustic products to be used for power and room acoustics.

I need help in sound isolating this room to reduce the amount of sound that leaks the room. There is bedroom upstairs and prayer room right next to it.   

I have been told that putting half inch spacers between lumber and drywall would help reduce the sound energy. 
1. What products can I use in between the wood frame and dry wall for reducing transmission of sound outside of the room?
2.  Can we replace drywall with some other product for sound isolation?
3.  Other suggestions or solutions would be appreciated as well.

I would not want to further drop the ceiling let's say more than an inch or so as the ceiling height is standard 8 feet

Thank you so much in advance for all your good help.
Timelines are tight - we have get the drywall in within a week or even less.

Regards
Sunil

[WGH]

Sound is like water, it will easily flow through the smallest hole so make sure your room is sealed up tight. A heavy door that seals on all four edges will contribute to household peace and harmony.

Check out the soundproof door thread:
http://www.audiocircle.com/index.php?topic=74124.0

Wayne

[Nyal Mellor]

SO many ways you can go about soundproofing.

Really the way to answer this is to ask what are you trying to achieve.

[bpape]

PAC Intl makes clips for your application that hold hat (firring) channel and decouple the drywall from the framing. You're going to lose more than 1" though - usually more like 1.25-2".

RSIC-V is more budget minded and loses less space. RSIC-1 takes up a little more space but decouples a bit better also.  You'll also need to use 2 layers of drywall with Green Glue between the layers.

Also, you need to pay attention to minimize and/or address any openings in the room like switches, outlets, lighting, HVAC, etc.  All of those are easy paths for noise to get out and propagate to other spaces in the home.

Bryan

[saisunil]

Thanks Wayne for the door suggestion - That would mean replacing the current french doors   

Thanks Bryan for the pointers - will look into as well

Also  I am wondering if there is solution for the roof like:

Frame -> Clip separator -> fancy sound proofing drywall or some magic poly spray or green glue and then regular drywall or fancy drywall

Super thanks

[WGH]

Thanks Wayne for the door suggestion - That would mean replacing the current french doors   

The easiest french door solution would then be to use the applied Pemko weather stripping found in my link above. You may have to put in a nice wood threshold so you can get a good seal on the bottom. What is the glass thickness? 1/8"? If there is room, remove the glass stop and replace the glass with a thicker laminated glass, 1/2" would be ideal. Expensive? Yes, but effective.

Mass is very effective at damping sound. Has anyone tried using a combination of cement board and drywall with Green Glue?

1/2" thick standard drywall weighs 1.7 lbs per square foot (54 lbs.)

1/2" thick cement board (Hardie Board, Durock) weighs 2.6 lbs per square foot (83.2 lbs)

[bpape]

That's basicaly what this is - frame->clip->channel->drywall-?Green Glue->drywall

Sure you can use cement board - you'd just need to beef up how many clips to support the additional weight.

Let me know if you have any problems finding those items...  

Bryan

[saisunil]

I am looking at the quiet rock drywall solution - impressive STC ratings from STC 50 onwards

http://www.quietrock.com/drywall.html

Question is how to I seal the recessed light fixtures as I see they are easy holes for sound leaks - apart from the door.

Thanks all

Keep it coming  .... I do realize that I will be barely scratching e surface of sound-proofing. Better do something instead of nothing.

My constraints are limited budget, can't lose too much space and can't have this project run for too long. Perhaps these constraints will only be good for me 

[bpape]

You can do that but to get those numbers, you need to use the stuff that's like over 1" thick which is a ***** to hang and handle and costs a small fortune to ship.  Standard drywall and Green Glue give pretty much the same result with much easier ease of handling, shipping, hanging, cutting, etc.  The only drawback is you  have to do it twice. 

Can lights are kind of defeating the purpose as you're sealing the shell, providing the mass and isolation, then cutting big holes in what you just did.  You can do soffits around the perimeter after the room is drywalled and put the cans in there so you're not piercing the shell.  Maybe a couple of GOOD track lights for middle of the room lighting. Cheap ones will rattle and buzz like crazy.

Bryan

[saisunil]

Our contractor prefers the quiet rock. It is like half a dozen in one and 6 in the other ...

Two layers of sheet rock and green glue on one hand and pre-made sandwich in the quite rock.

We are probably going to go with quite rock but appreciate your suggestion

Too late with recessed lights - they have already been installed - we will do what we can

[bpape]

Make sure the can lights are IC rated. Build an MDF backer box around them with only a hole in the front for the light and a small one for the Romex to enter.  That will give you 90% of the isolation back.

Bryan

[saisunil]

Make sure the can lights are IC rated. Build an MDF backer box around them with only a hole in the front for the light and a small one for the Romex to enter.  That will give you 90% of the isolation back.

Bryan

Thanks bryan

Also we are going back to the green glue solution as the quiet rock does have special requirements for special putty and special insulation etc for it to perform at the STC rating.

Perhaps the STC ratings are the MAX STC - not minimum ... Learning continues ...

Muchas gracias

[ctviggen]

Thanks bryan

Also we are going back to the green glue solution as the quiet rock does have special requirements for special putty and special insulation etc for it to perform at the STC rating.

Perhaps the STC ratings are the MAX STC - not minimum ... Learning continues ...

Muchas gracias

STC really isn't meant to capture music and particularly low frequency sound.  An STC only uses 16 standard frequencies, starting at 125 Hz:

http://en.wikipedia.org/wiki/Sound_transmission_class

So, STC ratings have some use, but aren't perfect as far as sound for music/movies goes.  Nonetheless, they provide some way to compare structures but it's better to build a wall with more mass and more isolation even if the STC is the same.  For instance, a wall with two layers of fire-rated drywall is better than a wall with two layers of regular drywall, even if the STC ratings are the same or close.  (And if you've ever lifted sheets of these, you can easily tell why -- regular drywall is nothing compared to fire-rated drywall.)

These people who build nice home theaters go to the extent of building columns for uplighting and electrical connectors that don't penetrate closed envelope of the room.  They minimize the penetrations into the room, and this is one way to do it.  That's great for a home theater, which doesn't need much light, but recessed lighting is going to give you much better coverage and better task lighting.  But then you have to spend a lot of time and money creating a box for each light, get AT and perhaps IC lights, etc.  You may also want to consider normal voltage recessed lights and not low voltage recessed lights, as the latter can buzz (or you at least should buy one and see if there's any sound from them while in use).

[ctviggen]

I'll give you an example.  The room I redid is about 23x16, and I used 12 recessed lights (6 inch, 75 watt bulbs) to cover the main area of the room (where my kids play).  And I still have dark spots towards the corners and edges of the room. 

[saisunil]

It is too late to choose different lights - recessed lights have been installed - we will have to enclose each light in a box and add some insulation. these will use the latest LED type ... We have not moved in ... So we have no opportunity to test which bulb types may be noisy but the electrician has a home theater himself and is sensible type who does not believe in wire type and all The other stuff I worry about 

ctv I appreciate your good suggestion of increasing mass.
So now I am going for high mass sheet rock green glue and another high mass sheet.

Thanks

[tasar]

I used Ecocell batts with single layer Soundbreak XP Gypsum board both sides of studwall.....these are 2 products needing more attention... Ecocell batts in many thickness choices.... The structure of this batt makes it rather rigid much more so than 703/705.....I'm considering this product for my bass traps and similar absorption types faced w kraft paper membrane and 1" false back void. Another product worthy of mention is the Thermafiber SAFB.... Roxul knockoff at half the price. Home Acres is a source in the
Midwest and NO, I do not work for them! Has anyone ever sourced "white faced builder's board" ?

[ctviggen]

It is too late to choose different lights - recessed lights have been installed - we will have to enclose each light in a box and add some insulation. these will use the latest LED type ... We have not moved in ... So we have no opportunity to test which bulb types may be noisy but the electrician has a home theater himself and is sensible type who does not believe in wire type and all The other stuff I worry

The noisiness of low voltage cans is caused by a transformer, which drops the voltage down to low voltage.  LEDs may use a different technology.  And, you can use a high voltage recessed "can" and just add in an LED "bulb", which has its own voltage reduction circuitry.  Or, you can buy a recessed fixture (aka "can") that's designed only for LEDs.  In your case, it sounds like the electrician knows what he's doing, so that's great.  Enjoy your room!

By the way, when I redid my room (the one with the 12 recessed lights), I had some low capacitance speaker wire cryogenically treated.  I used the cryoed stuff for the front three speakers and the non-cryoed stuff for the surrounds.  Even with long speaker runs, the sound system sounds great.