Old 2 pane Window glass

Tom Zartler · Post by **Tom Zartler** » Fri Dec 03, 2004 2:53 am

My neighbor is replacing his windows today and they are throwing out the old windows and I was wondering if 2 pane 1/4" windows could be used in my studio in either the control room window or the window that lets you see in from a hallway. I did some searches and I don't know how to classify the old windows.

thanks,
tom

Tom Zartler · Post by **Tom Zartler** » Fri Dec 03, 2004 3:04 am

Ok, I think I found it. These types of windows are called "Double Glazed"? And the closeness of the 2 panes causes problems with the sound including the spring effect of thinner glass?

Is that right?

Tom

knightfly · Post by **knightfly** » Fri Dec 03, 2004 10:32 am

Right - depending on the thickness of the glass and the distance between panes, you'd have (using just one of these) a resonance at 150-250 hZ (weak point) and an STC of somewhere between 30 and 38, with only about 17 dB of TL at the low end even with heavier/thicker versions.

Adding a second one will reinforce the same weakness, as well as introduce another dip in isolation at a different frequency dependent on the air gap.

If you have a NON-studio use for these, fine - but there are times when "free" isn't a good deal... Steve

motown59 · Post by **motown59** » Sat Dec 04, 2004 4:14 am

I bet they're replacing their windows with something better. The older aluminum dual pane jobbies are terrible. I have been addressing that issue in my guest-house turned studio. I sealed off one window and was looking into replacements. I ended up ordering a Windowmaster vinyl dual pane with their 'sound control' option. It's states a 20% increse in performance over their regular vinyl windows...which I've been happy with in my previous home near the freeway. Home Depot can special order them. It's said to be a 40 STC window which is probably good enough for me for what I do. the occasional drum thing will be during the day and neighbors are 100' away. Cost for a 6040 was about $350 for a nail-on. Milgard has similar and more isolated( up to 46 STC) windows going up to $700 for that size. FYI

Tom Zartler · Post by **Tom Zartler** » Sat Dec 04, 2004 2:17 pm

Thanks for the info. I had a feeling that free was too good to be true!

So My studies continue... Now, for my next question in a new thread.