If you used laminated glass it would be different sizes. Usually laminated glass is either the inside or outside glass pane, not both.

As you thought, "lite" is simply a term used to describe one sheet of glass.

The most common thickness of laminated glass in North America is probably 3mm / .76mm / 3mm.

Impact products increase the interlayer to 2.29mm and might use any glass thickness from 3mm to 6mm depending on the application.

Using different thicknesses of glass in a laminated make-up will have some affect on sound propagation. Monolithic laminated glass at any make-up will be a noticeable improvement over a single lite of annealed glass. A laminated glass make-up of 3mm / .76mm / 5mm should perform very well in sound application.

Your mom and pop shop folks are not correct when they say that the frame is more important than the glass make-up - however, a tight frame and rigid construction will be much better than a loose frame and sash assembly.

If the window leaks air, it will pass sound.

I had some really bad double pane window, they were gas filled also, they didn't have much space between the glass and I think the new windows glass is actually thicker also. It has been a world of difference on noise reduction since my new windows were installed. I can't quote #'s though but the amt. of space between glass and thicker glass, new windows also have what is called a solar sheild between glass and argon gas, not sure if that helped also.

Huggy, did you find a supplier of noise reduction windows in Taiwan? If so can you share the info. I live in Taiwan also and I'm looking for this type of window,

Thanks