Foggy Glass Between the Panes — Failed Seal, Sealed Unit Replaced
Haze, cloudiness or water drops between the two panes of a double-pane window is a failed seal: the insulated glass unit (IGU) let humid air in, and it condenses on the inside faces you cannot reach. The frame is fine. We measure the opening, build a new sealed unit to that exact size — rigid aluminum spacer packed with desiccant, butyl sealed around the full perimeter — and swap only the glass, $198 to $480 per unit depending on size and glass type. Rainbow or oily-looking stains inside the glass are the low-e coating corroded by that trapped moisture; they never wipe off and mean the seal failed a while ago. Charlotte homes built in the last few years fog early because builder-grade units use foam or U-channel spacers with very little desiccant — our replacement unit routinely outlasts the factory original.