Best construction for framing new VO Booth Glass?

[ernest savage]

Hope this is where you post new threads.

I'm finishing a VO Booth. I need to frame in a 1/2 laminate window. I have an existing double pain window, but the STC rating is not high enough. I'd like to install 1/2 laminate glass 2 inches away from it, creating a 2" air gap. I have a few questions.

Existing window and frame:

https://www.dropbox.com/s/frmd98lidfhy9o5/existing vo booth window.jpg?dl=0

I think I should reframe the window sill, using 1/4" mass load vinyl to separate the new wood from the existing wood and glass. Place the new laminate glass in a sandwich frame, and place that frame on top of the new window frame.

Step 1:

New framing area:

https://www.dropbox.com/s/zqow36jjazr0pah/VO Booth Glass 1.jpg?dl=0

Glue 1/4" mass load vinyl around the existing window frame, and up the glass 2" around frame, creating an "L" shape of vinyl for the the new 2"x6" hardwood window frame to sit on.

Finish nail, and use a few screws to place new 2"x6" frame around existing frame on top of new vinyl. This new frame will extended the space available to sandwich new glass with a 2" air gap, and still have enough room to nail/glue last piece of sandwich frame around glass.

Step 2:

New laminate glass sandwich:

https://www.dropbox.com/s/fd44cmqhkt8tlry/VO Booth Glass 2.jpg?dl=0

Cut a 2"x4" hard wood in half to create two 2"x 2"s. Finish nail/glue the first 2"x2" against new window frame and existing window. Place silica? beads for moisture. Glue new glass into place. Finish nail/glue last 2"x2".

Questions:

1. The specific name of the "acoustic glue" I should use to seal the window? I see all kinds of references to acoustic glue, but no names. Green glue says it is NOT an adhesive, so can that be used?

2. Does my new wood need to be 2"s thick? Would 1" suffice? Should I use hardwood like Maple or Oak? I'm thinking only of sound transmission, as I will be painting the wood. MDF instead?

3. I'm pretty sure I need the mass load vinyl to separate the new window frame from existing wall, however, should I add mass load vinyl again, after the new frame and before the window sandwich? I have 1/8" mass load vinyl I could use as well.

4. Anything else I'm doing wrong?

 

[witzendoz]

Ideally you would have 2 separate frames, but I would sit a new pane in the window frame between an inside and an outside (of pane) square wooden baton. Sit the glass on neoprene strips to take up the gap and use neoprene on the inside of the batons and to add some isolation. This will be fine.

Alan.

 

[ernest savage]

Hi Alan,

Thanks for your response. So I shouldn't worry about an adhesive for the glass, as I sandwich it in a wood frame?

 

[witzendoz]

Hi Alan,

Thanks for your response. So I shouldn't worry about an adhesive for the glass, as I sandwich it in a wood frame?

Sandwich it in the frame with the neoprene between the wood and glass. The neoprene only needs to be front & back, I got sticky back neoprene and stuck it to the inside of the wood batons. I used a few neoprene packers under the bottom edge of the glass to lift it off the frame a little. Allow clearance between the glass and frame to help with fitting.

A couple of screws through the baton into the frame will hold it in place. The baton goes around the top, bottom and sides of the frame inside and outside of the glass.

If I get a chance tonight I will take a photo of my window as it is installed.

Alan.

 

[witzendoz]

I have attached some photos of my glass. The 2 panes are mounted on separate frames installed in separate stud walls. The glass on the recording side in my case is also angled, but you don't need to bother about that. You can see the neoprene strips between the square wood batons and the glass.

Hope this helps.
Alan.