Water pipes usually burst because something has put the pipe or one of its joints under more strain than it can take. Common causes include water freezing inside the pipe, ageing or corroded pipework, accidental damage and joints that have weakened over time.
Often more than one factor is involved, so the exact cause usually needs to be checked when the pipe is repaired. Knowing why it failed can help stop the same thing happening again.
Freezing Weather
When water freezes it expands. If this happens inside a pipe, the pressure can split the pipe or push a joint apart. The damage is not always obvious straight away, because the ice can hold the water back. The leak may only show once the pipe thaws.
Pipes in lofts, garages, outbuildings, outside walls and unheated rooms are usually more exposed. Cold snaps can still happen in Poole, and homes that are left empty or unheated can be more at risk.
If you think a pipe has frozen, avoid using a naked flame or high heat to thaw it, as this can damage the pipe or cause a fire.
Age, Wear and Corrosion
Pipework does not last forever. Over time, some pipes and fittings may corrode, wear thin or become brittle, depending on the material and conditions. A weak point may hold for years and then fail suddenly, sometimes after a change such as a rise in pressure or a knock.
This does not mean every older pipe will burst. The condition of pipework varies a lot from one property to another.
Damage and Movement
Pipes can be damaged by a nail or screw during DIY work, by building work, or by being knocked in a cupboard or loft. Pipes that are not properly supported may also move each time water flows, which can put strain on joints.
Changes in water pressure can also add strain, for example if pressure rises after work on the supply, although pressure alone does not usually explain a burst without another weakness.
Joints and fittings are common weak points. A joint that was not made well, or one that has been disturbed, may start as a small leak and then fail more suddenly.
Reducing the Risk
Some simple steps can help lower the chance of a pipe bursting:
- Insulate pipes in lofts, garages and other cold spaces
- Keep some heating on in cold weather, especially if the property will be empty
- Know where your stopcock is and check it turns
- Take care when drilling or fixing into walls and floors
If a pipe does burst, a repair will usually look at both the damaged section and the reason it failed. Our page on burst pipe repair in Poole explains how these repairs are approached.
If you are worried about a pipe that has split or a joint that has failed, a plumber can look at the damage and explain the repair options.