Cracked Window: Should You Repair or Replace It?
12 April 2026 · 4 min read
A crack doesn't always mean a new window. Here's how to tell what actually needs replacing — and keep the cost down.
Single pane vs sealed unit
If you have older single-glazed windows, a crack usually means replacing just that one pane of glass within the existing frame — a quick, affordable job. With double glazing, the two panes are sealed together as a unit, so a crack in one normally means replacing the whole sealed unit, not the frame.
Either way, the frame itself almost always stays. That keeps the cost far lower than a full window replacement.
When a crack can't wait
Treat a cracked pane as urgent if it is on a door, a ground-floor window, or anywhere it affects security. Cracks also spread — temperature changes and a knock can turn a hairline crack into a shattered pane. Toughened safety glass that has cracked should be replaced promptly, as it can give way suddenly.
In the meantime, avoid pressing on the glass and keep the window closed.
Getting it sorted
A glazier measures the pane or unit, confirms the glass specification (including any safety glass requirements), and fits the replacement — often the same day for standard sizes. You keep your frame, and the window is back to full strength and insulation.
We provide a free written quote and can advise whether a repair or a new unit is the better value for your window.
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