What a broken seal means
A double-pane window is a sealed unit: two sheets of glass with a spacer and seal around the edge, often filled with insulating gas. Over years of sun and temperature swings, the seal can fail. Moist air then gets in, condenses when the glass cools, and leaves fog or mineral streaks.
Fog on the room side or outside face isn't a broken seal. That's normal condensation and it wipes off.
Can a broken seal be repaired?
Defogging services drill small holes, dry the unit out and plug the holes. That can improve how it looks for a while, but it doesn't restore the seal or the insulating gas, so the problem often comes back. The lasting fix is replacing the sealed glass unit.
You usually don't need a new window
Sealed glass units are made to be replaced on their own. The frame, sash and hardware stay. The new unit is made to your exact size, and you can often upgrade to low-E coated glass at the same time.
When to call us
Call when you see fog between the panes, white streaks inside the glass, or a cold spot near one window. We measure the unit, order it to size and fit it, usually in two short visits.
Questions
Does a broken window seal waste energy?
Some. Once the seal fails and the gas leaks out, the window insulates less well, but the bigger complaint is usually that you can't see through it.
Is a broken seal covered by warranty?
Many windows carry a warranty on the sealed unit. Check your window's paperwork or label before paying for a replacement.