Sometimes IG panel seals will fail. When this happens, the panel will fog. If the panel has not been properly supported, or if the leaded panel is heavy, it is possible for the panel to drop in the insulated unit, as well. A panel dropping in the unit can also cause fogging, as it will sometimes break the seal. The only way to fix fogged and dropped IG units is to re-insulate the units. If panels start fogging, it is recommended the panels get fixed right-a-way, or the moisture will start etching the glass, which raises the price of repairing the IG unit back to its original condition.

Fogged IG Unit

Dropped leaded panel inside IG unit