Control Room Glass

[kidego32]

Hi Guys,

I have two options for the window dividing the control and live room. I can create an insulated unit in one of the leafs of the dividing wall by using a sheet of 1/2" Laminated glass and a sheet of 1/4" Laminated glass, with 4" of space between them. This would be on the wall leaf facing the live room.

On the wall leaf facing the control room, I can use either 1/4" Laminated glass or 3/8" Laminated glass.

The other option would be to use 1/2" Laminted on one leaf and 1/4" or 3/8" Laminated on the other.

Would the 1st option provide a vast improvement, or should I stick to the seoond option?

Jules

Follow up: This is a cross-section of how I'm planning to install the glass. Notice the two panes of glass on the right leaf, and one pane on the left leaf.

[Sen]

Hi Jules,
If I'm reading the drawing right, you're creating a triple-leaf-system with your glass panes which is no good!It's the best to have one pane of glass on each side, as thick as possible but different thicknesses if possible..
cheers

[kidego32]

Hi Sen,

Thanks a bunch for your reply. Yep, you read the drawing right! I'm glad I asked 'cause I was going to go with 3 panes of glass, thinking it would be superior as a sound barrier.

Again, thanks.

Jules

[Sen]

Hi kidego,
no worries...glad I could help...just saw something else about windows..could be worth having a read

Guys,

I'm reading a report about sound isolation with double leaf constructions from the Leuven University(geluidsisolatieverbetering met voorzetwanden, G. Vermeir, P. Mees).

Here is something about windows constructions with very high sound isolation:

They advice a totally seperated construction where you have two brick walls, with in 'm a fixed window with a 12mm glass-12mm gap-6mm glass, then an air gap of 230mm, then a double sealed window that can be opened with a 12 mm glass pane in it.

So in fact a triple leaf construction with a very narrow and a very large airgap.

The R values (Hz-dB):
100 - 45
125 - 49
160 - 45
200 - 46
250 - 51
325 - 54
400 - 57
500 - 61
630 - 64
800 - 67
1000 - 68
1250 - 71
1600 - 73
2000 - 69
2500 - 69
3150 - 67

So: seems that when you have a good thermopane window you don't always have to replace it if you want to avoid a triple leaf construction.

Bert

written by another member here bert stoltenborg

[knightfly]

That post by Bert was in reference to an EXISTING condition, as to whether the thermpane should be removed - for NEW construction, you should ALWAYS stick to the 2-leaf method as Sen first posted; note that in the TL values in the table, there is a dip in isolation between 125 and 250 hZ? This is a small example of what 3-leaf construction does; there will also be a point higher up in frequency where the 3-leaf is BETTER than two, but for low end it's always WORSE. And, since the low end is the hardest to get right for music, that's what you should design for.

As to tilted glass, check THIS -

http://www.noisecontrol.net/myths.html

[bert Stoltenborg]

Steve is right.

When you want to know this kind of stuff you should calculate the final isolation.

For new construction NEVER go three leaf!