Why is water running on the inside of your double glazing?

Water running on the inside of double glazing typically indicates a failure in the seal between the glass panes, allowing moisture to enter the insulating space. This moisture condenses on the inner surface of the glass, leading to water accumulation. Proper functioning double glazing should prevent this issue by maintaining a dry air space between the panes. If you experience this problem, it may be necessary to replace the window to restore its insulating properties.