Window Glazing and the various benefits

Many people do not understand the various types of widows, the benefits and possible drawbacks.  First, you have traditional single windows: these windows have a single pane of glass and an R value of 1.  The R value is a measure of the windows resistance to heat loss.  The second type of widow is the double glazed consisting of two panes of glass with gas between them.  This type of window has twice the resistance to heat loss as the single pane window yielding an R value of 2.0.  Depending on the type of window, number of panes and type gas filled between the panes of glass, the R value can be increased as well as the price.  Be sure to weigh the benefits.

One negative aspect is that the seal between the panes of glass can leak and cause cloudy windows.