Double Glazing Window Repairs If your double-glazed windows are faulty, you need to have them repaired as soon as you can. If the seals have been damaged, it could cause draughts and condensation, and make your house less efficient on energy. Repairing double glazing is usually cheaper than replacing it. https://www.repairmywindowsanddoors.co.uk/walthamcross-windowrepair/