Sound deadening for walls & ceiling

[Mr Pookie]

Hi there,

Okay, as I'm having a new house built with a custom home theatre room tailor made to my needs (4.7m x 5.8m), I've been looking around for some sound deadening materials to put into the surrounding walls and ceiling to stop all the neighbours from hearing it.

Anyone (perferably in oz) know of a good yet not too expensive product to use here for the insulations?

[ultrachrome]

Is it correct to assume that at least one wall of the room borders the exterior? If so, you probably need to focus on isolating the interior wall from the exterior using resiliant channel or fastening the interior drywall to studs that are not in contact with the exterior surface.

If you have the interior drywall fastened to the same piece of structure that the exterior siding is fastened to, sound will conduct right through the wall.

For wall cavities, there is fiberglass insulation that is rated for sound deadening.

Based on some light reading I've done, depending on how much attenuation you need, you have to approach making the room as airtight as possible and all interior surfaces must be mechanically isolated from the greater structure. Think a box within a box.

Resiliant channel can be used on walls and ceilings which is effectively a spring that helps prevent vibrations in the drywall from passing to the structure.

[Mr Pookie]

The room is at the mid front of the house, with the garage to the left, a hall to the right, the kitchen at the back, and the front wall is the front of the house, which has 2 large windows. ( a single door runs from the hallway mid way along the wall) And the floor will be thick carpeted (maybe black)

It's a standard plasterboard for all interior walls, with a single brick veneer for the outside of the house.

I haven't decided yet, but might cover the whole front window area with an artificial wall to stop the light and to add extra dampening of the wall. Also, the room will be air conditioned with a split system above the window area...

So the best option is to run these Resilient metal strips around all the walls, and putting fibreglass batting in all the gaps between the studs? And would this be enough to make the sound unnoticable to the outside world?

[ppfred]

Originally posted by Mr Pookie
Anyone (perferably in oz) know of a good yet not too expensive product to use here for the insulations?

Hi,
Sound will conduct through a wall regardless of the insulation you use. It travels through solids: drywall attached to studs attached to drywall, etc....
What you should do is build a secondary wall frame detached from the original wall, i.e., with an airspace between them, and then fill the space with sound absorbing insulation. The down side is that you lose a lot of floor space.

Another option not as efficient as above but it saves a lot of room area, is to use 2x3 vertical studs on the 2x4 horizontal plates, and stagger the 2x3's at 16" centers. Then you could weave the sound absorbing insulation horizontally through the interior of the wall - e.g.,
______________
x 16 x 16 x 16 x
16 x 16 x 16 x 16
¯¯¯¯¯¯¯¯¯¯¯¯¯¯
The solid lines represent the horizontal 2x4.
The x is the 2x3 vertical stud
The 16 represents the spacing.
Anechoic it's not but close.

I realize that you guys use metrics, so do the conversion....
I hope this makes sense. Without CAD drawings it's the best that I can do.

fred p.