Repairing Double Glazed Windows When Double-glazed windows "blow" they let the gas that insulates them, argon, escapes, causing them reduce their energy efficiency. The good thing is that damaged double glazing is typically repaired without the need to replace the windows. Moisture or condensation in between your double glazed windows https://www.repairmywindowsanddoors.co.uk/chiswick-windowrepair/