Well, look at it this way.... The double glazed windows are two seperate sheets of glass set in a metal frame with an airspace between which is either evacuated to a near vacuum or filled with an inert gas (which I'm sure you already knew). The metal frame still conducts cold between the two sheets of glass on the borders. It's not nearly as conductive as a single sheet of glass, but notheless, the area on the glass near the metal is colder and moisture in the home condenses. It can help, of course, to attack the source of the moisture in the home in the first place. If the condensation is worse in one room than another, try running a dehumidifier in that room. Secondly, set up an inexpensive fan near the windows to circulate the air. By the way, here in the U.S., some of the double glazed windows are set in plastic framing, which seems to help, but still doesn't totally end the problem... Best of luck!