I have a large single-pane window in my den (side-by-side slider) that
transmits road noise.

I thought of replacing it with a new dual pane (thermopane) window to reduce
noise transmission.This means ripping out the old window & frame.

Another route to go is to place a duplicate inside window on the inside sill
of the existing window, like an interior storm window.

This site claims that a double-window is superior in suppressing noise than
a single thermopane window. http://www.soundproofwindows.com/comparison.html

Is this only salesmanship? Any opinions?

--
Walter
www.rationality.net
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