Soundproofing a window

[Chaotic42]

I have the need to sound proof a fairly large window (About 4'x7' by my estimation). Originally I was just going to take a piece of plywood, staple black cloth to it, and nail it to the wall around the edges (The window is recessed about 4"), but I was thinking that it might work better if I put some kind of sound-proofing foam on the face of the plywood toward the window.

What kind of material would be fairly cheap and effective? The window doesn't really need to ever be opened. Where can I find soundproofing material? Any recommendations?

 

[Quasmo]

the more glass the better fill the space between them with argon gas

 

[TheoPetro]

Originally posted by: Quasmo
the more glass the better fill the space between them with argon gas

better yet as close to a vaccume as you can get

 

[bctbct]

you could use rigid foam between glass and plywood. Foam would probably be best and you could paint it black. If you want you could put sound sealant around the foam to the window unit to maximize sound barrier.

 

[Beau]

I've also heard that you should angle the panes away from eachother, not sure if it's true though... like: /|

 

[MikeyIs4Dcats]

Originally posted by: bctbct
you could use rigid foam between glass and plywood. Foam would probably be best and you could paint it black. If you want you could put sound sealant around the foam to the window unit to maximize sound barrier.

batt insulation is a better sound insulator

 

[Quasmo]

Originally posted by: Beau
I've also heard that you should angle the panes away from eachother, not sure if it's true though... like: /|

this is true if you put them going the same direction its easier for sound to travel through, but if you angle them its harder.

 

[MikeyIs4Dcats]

by the way, are you trying to keep sound in, or keep it out? it will make a difference on the best way to handle it

 

[fitzov]

egg cartons/coffee cup holders?

 

[Chaotic42]

Originally posted by: MikeyIs4Dcats
by the way, are you trying to keep sound in, or keep it out? it will make a difference on the best way to handle it

Out.

What if I sandwhiched the soundproof foam between two pieces of plywood?

 

[MikeyIs4Dcats]

Originally posted by: Chaotic42

Originally posted by: MikeyIs4Dcats
by the way, are you trying to keep sound in, or keep it out? it will make a difference on the best way to handle it

Out.

in this case, you need to put the absorbant material on the "noisy" side of the plywood. Call around to the building materials dealers in your town and see if anyone has "sound batt" insulation. If not, just get some regular R-19 insulation and cut it to fit the window opening. Also, if there is room, putting thin foam rubber glued to the plywood could help. So you will have

glass*batt insulation*(foamRubber)*plywood. Caulk the edges of the plywood to the wall if you are able.

Avoid putting a hard surface between the glass and the batts. You need the soft material to absorb the sound waves coming off the glass. And do not use rigid foam. The rigidity will help transmit sound through the foam. You want loose fibers like batt insulation.

Can you do anything to the exterior of the window? I'm assuming this is on an outside wall and the answer is no.