Emergency Glass Repair: What to do when glass breaks.

Broken glass is stressful. The good news is that handling it well is mostly about following a sequence – secure the area, document the damage, board up, then call a glazier. We do this five times a day across Greater Sydney; here’s the guide we’d give a friend.

What causes glass to break?

Knowing why it broke matters – for insurance, for prevention, and for choosing the right replacement spec.

1. Impact damage. A thrown ball, a stone from a mower, a bird, a forced-entry attempt. The most common cause we see.
2. Thermal stress. Hot sun on cold glass, or cold air on a hot pane – sudden temperature change creates internal stress that the glass can’t absorb. Often happens in the first cold morning of winter.
3. Poor installation or frame pressure. Glass that’s been pinched in the rebate, or a frame that’s shifted with the house, can crack from edge stress.
4. Manufacturing flaws. Nickel sulphide inclusions in tempered glass cause spontaneous shattering – rare, but real. Manufacturers replace under warranty.
5. Structural movement. Heritage timber-framed homes flex over time. A long-static window can suddenly get loaded as the house moves.
6. Old or worn seals. Failed glazing tape lets the glass move in the rebate – it eventually cracks at the bearing point.
7. Spontaneous breakage. Tempered glass that fails for no obvious reason – this is the nickel sulphide story above.

What to do immediately after glass breaks

Six steps. Do them in order.

1. Stay calm and assess

• Check yourself and others for cuts
• Identify children, pets, bare-foot adults – clear them from the area
• Note whether it’s an external pane (security/weather concern) or internal
• If anyone is bleeding or there’s ceiling glass falling, call 000 first

2. Secure the area

• Close off the room if you can
• Wear closed shoes — ideally with a hard sole
• Leather gloves if you have them
• Don’t walk in stockinged feet anywhere near the breakage
• If the glass is overhead (skylight, conservatory) get out of the room – falling shards can keep coming for hours

3. Clean up carefully

• Stiff broom and dustpan for the bigger pieces
• Vacuum the area after – but empty the canister outside (glass dust travels)
• Damp paper towel picks up tiny shards a vacuum misses
• Bin the lot in a thick plastic bag, double-bagged

4. Cover the damaged area

• Plywood is gold standard for external openings
• Thick cardboard + tarp + gaffer tape if you don’t have ply
• Don’t leave a broken external pane overnight in winter or storm season

5. Document for insurance

• Wide shot showing the room and damage location
• Close-up of the break itself
• Cause if visible (the brick, the bird, the stone)
• Photos of any related damage (carpet, walls, contents)

6. Call a professional

• Look for a glazier with same-day boarding capability
• Confirm they handle insurance claims (most reputable ones do)
• Ask about glass spec – replacement to original spec is the minimum, an upgrade to AS2208 safety glass is the smart call
• Get the quote in writing before any work starts

How to prevent future glass breakage

• Inspect frames and seals annually. Cracked silicone, perished glazing tape, rust at the corners – all warning signs of imminent glass failure.
• Install protective films. Window film adds significant impact resistance to single-pane glass, and slows the propagation of cracks if they form.
• Spec safety/laminated glass for high-risk locations. Anywhere AS1288 mandates it, and any other location prone to impact (low windows, sport-adjacent spots).
• Manage indoor temperature. Don’t blast hot air on cold glass – that’s how thermal stress cracks form. Curtains help.
• Trim trees back from glazing. Branches in the wind crack glass. Trim regularly.

Typical costs of emergency glass repair in Sydney

Approximate, supplied and installed, taken from our 2025 jobs:

• Standard residential single-pane (3–6mm) replacement: $250–$600
• Toughened safety glass (4–6mm): $400–$900
• Laminated safety glass (6.38–8.38mm): $600–$1,200
• Sealed double-glazed unit (IGU) replacement: $600–$1,800
• Same-day emergency boarding: $150–$300 (often included free with replacement)
• Architectural glazing (large panels, frameless): $1,500+

Most house insurance policies cover accidental glass breakage. We coordinate directly with insurers – quoting, documentation, replacement.

Emergency glass repair checklist

Before the glazier arrives, save time by having these ready:

• Photos of the damage (wide and close-up)
• Insurance details (provider, policy number)
• The cause if you know it
• Original glass spec if visible (etched mark in corner)
• Access – clear the area in front of the broken pane
• Power outlet nearby for tools

Final thoughts

Move fast on emergency glass – but move methodically. Secure first, document second, board up third, call us fourth. We’re on 1300 854 726 any time of day or night.