A burst pipe is dramatic when it happens in the open, with water gushing across a floor. More often, it starts as a slow leak inside a wall, ceiling or slab and goes unnoticed for weeks. Either way, the water has to be stopped quickly, and the cause understood, so it does not simply happen again elsewhere.
Why pipes burst
- Age and corrosion. Older metal pipes can thin from the inside, particularly at joints and bends.
- High water pressure. Constant high pressure stresses pipes, fittings, hoses and appliances. Pressure can vary between streets and between floors.
- Water hammer. A sudden shock when a tap or valve closes quickly can loosen joints over time.
- Poor workmanship or materials. A badly made joint or an unsuitable fitting can fail years later.
- Movement and damage. Settling ground, tree roots, building work and accidental impact can crack pipes.
- Flexible hoses. The braided hoses behind basins, toilets and washing machines are a very common source of bursts, and they wear out.
Signs of a hidden leak
- Damp patches, paint bubbling or staining on walls and ceilings.
- A musty smell with no visible cause, or mould appearing in an unusual place.
- The sound of running water when everything is off.
- Warm patches on a floor, which can indicate a leak in a hot water line.
- A water bill that rises with no change in use.
Turn off every tap and appliance, then look at your water meter. If the dial or reading keeps moving, water is going somewhere. Close the mains isolation valve and check again: if the meter stops, the leak is on your side of it. A plumber can then locate it with proper equipment.
What to do when one bursts
Close the mains isolation valve, switch off power to an electric hot water unit, keep clear of electrics, and contain the water. The full sequence is in the emergency guide and the first five minutes. Photograph everything before it is repaired and contact your insurer if damage is significant.
How burst pipes are repaired
Repair options depend on the pipe, its location and its condition. A licensed plumber might fit a temporary clamp to stop a leak, cut out the damaged section and join in a new length, or replace a whole run if the rest of the pipe is in poor shape. Pipes under a slab or inside walls may need to be rerouted, which can avoid breaking floors but changes where pipework runs. Ask what caused the failure, whether similar pipes elsewhere in the house are at risk, and what paperwork applies to the repair. The wall, floor or ceiling then needs to be dried and made good, which is often a separate cost; see plumbing costs in Sydney.
Reducing the risk
- Know where the mains isolation valve is and check it turns.
- Replace old flexible hoses before they fail.
- Ask a licensed plumber whether your water pressure is within a sensible range, and whether a pressure limiting device would help.
- Do not ignore small drips, damp patches or noisy pipes.
- Be careful with building work and digging near pipes, including garden drains and taps.
- Think about a leak detector or a smart water monitor if you are away often.
If you rent, report any signs of leaks to the landlord or property manager in writing. If you live in an apartment, report them to the building manager, because water travels. And if you are weighing how to find someone, how to choose a plumber in Sydney gives a short checklist.