Well-made double glazing lasts a long time, but not for ever. The frames, the sealed glass units and the moving parts all age at different rates, and knowing which is failing helps you decide between a repair and a replacement.
Signs it is time to act
Condensation or misting between the panes means the seal on that glass unit has failed. Draughts, rattling, stiff handles or windows that will not lock usually point to worn hinges, seals or locks. Discoloured, warped or cracked frames suggest the frames themselves are at the end of their life.
Repair or replace?
A misted glass unit or a broken hinge can usually be fixed on its own, often in a single visit. If several windows have problems, the frames are damaged, or the windows are old enough that newer glass would make a noticeable difference to your heating bills, replacement is usually better value.
Making your windows last
Clean frames and tracks a couple of times a year, keep drainage holes clear, and put a drop of light oil on hinges and locks. Small jobs like these keep everything working smoothly for longer.