DIY sound proofing

[msrd]

Im about to start working with my contractor on building my home theater (8 seats)
I would like to know the steps for sound proofing the room

thanks

[bpape]

Is the room already framed? If not, there are a lot of things that can be done reasonably to help quite a bit.

Just remember that sound travels through the air and through the structure.

Decouple the room from the rest of the house as much as possible.

Seal ALL holes (outlets, switches, lights, etc.) or better yet, do them so they don't make holes in the sealed room

Use a solid core wood door with seals

Pay a lot of attention to how you're going to heat and cool the room as HVAC systems snake all through a house and transmit sound both ways very easily.

Bryan

[chadcummings]

Another note on the AC. Do NOT use the metal ductwork, you want to use the ductboard and make sure you have some Z turns in it to reduce sound transmission.

There are a lot of ideas on the board and most are not incorrect, just not the prefered methods. Many people cool the room and then have an air return above their projector where others vent at the projector and pull from another part of the room. Both will work; however, one can cause condensation on the projector.

Best advice is read, read and read and when you think you know, post your thoughts to see what advice you can get.

That is what I have been and are currently doing.

[bpape]

Agreed on the non-metal. Just also understand that ductboard won't provide isolation. The board needs to be inside a box structure with mating bends to provide the mass to stop bass passing directly through the ductboard.

In that type of construction, you can also use flex duct inside MDF boxing to provide the same effect.

Bryan

[chadcummings]

Agreed.

I planned on running my ductwork inside my sealed room in the soffit area. This ensures plenty of isolation while the ductboard prevents the high freqs from running through the house.

[Gregavi]

One Layer 1/2" drywall over 5/8" layer of drywall with Green Glue or Quiet Glue between the layers. Simple, effective. Not cheap, but less expensive than some methods that are not as effective. Staggered stud or double wall framing with the double drywall method.

[Ted White]

I realize this is an old thread, however, people pour through old threads like this for insight. In general:

Decouple the new drywall surfaces from the original framing via a decoupling means.

Add Absorption, generally R13 or R19 fiberglass insulation.

Add mass. This is a bargain using standard $8 drywall. Use double 5/8"

Add damping. Different materials used for this.

These are the 4 elements in play with soundproofing. This article may help clarify: http://www.soundproofingcompany.com/..._construction/