A burst pipe or overflow at night, and what to do first

When water starts flowing after hours

A burst pipe, a split flexible hose under the sink or a cistern that will not stop filling rarely happens at a convenient time. When it happens late at night, the pressure to fix everything at once can lead to rushed decisions, unsafe handling of electrics and an expensive call-out that was not needed.

This article covers the first few minutes: stopping the water, making the area safe and containing the damage. It then helps you decide what can wait until morning, when the right call is your Town Council or management office, and what to ask an after-hours plumber before they come. For slower leaks and how they are traced, the leak repair guide goes into more detail.

Step one: shut off the water

The fastest way to stop most leaks inside your home is to close the water supply to the unit or to the fitting that is leaking.

• Isolation valve at the fitting: many taps, toilets, water heaters and washing machines have a small valve on the pipe feeding them. Turning it closes the supply to that fitting only.
• Main valve for the unit: in many flats the main valve is near the water meter, often in a service duct, the corridor or near the kitchen. In condominiums and landed homes it may be in a utility area or outside near the gate.
• Water heater supply: if the leak is from a storage heater, close the cold water supply valve feeding it as well as switching off its power. The water heater guide covers repair and replacement once the leak is under control.

Find your main valve before you ever need it. Try it once so you know which way it turns and whether it is stiff, and tell everyone in the household where it is.

Step two: make the area safe

Water and electricity together are the biggest risk in a night-time leak. If water is near power points, extension cords, a water heater or appliances, switch off the power to that area at the DB box before you step into the water or touch anything plugged in. If you are not sure which breaker covers the area, switch off the main switch.

Once the power is off, move electrical items, rugs, documents and furniture away from the water. Lift what you can off the floor.

Step three: contain the water

With the supply closed and the area safe, the aim is to limit damage until a plumber can look at it.

• Put a bucket or basin under any dripping pipe or joint.
• Use towels to stop water spreading into bedrooms or under cabinets and doors.
• Mop or squeegee standing water towards a floor trap.
• Open windows and run a fan once the electrics are confirmed safe, to help the area dry.
• Take photos and a short video of the leak and any damage for the plumber and, if needed, your insurer.

If water may be seeping into the unit below, let your neighbour know. It is better they hear it from you than find a stain on their ceiling.

What can wait until morning

Once the water is off and the area is safe, many problems can wait for a normal daytime visit, which is usually easier to arrange and compare. The plumbing guide explains how to compare companies when you have time to do so.

• Usually safe to wait: a leak that stops when you close the isolation valve for one fitting, a dripping tap, a running toilet you have isolated, or a slow drip into a bucket that you can empty.
• Worth calling tonight: a leak you cannot stop with any valve, water reaching the DB box or electrical points, a leak from a pipe you cannot isolate, or a home where closing the main valve leaves you without water for something you cannot do without.

If you can isolate one fitting and keep the rest of the home supplied, waiting until morning is often the calmer choice.

When the problem is a shared pipe

If water is coming from a corridor pipe, a common drainage stack or the ceiling, the source may not be inside your unit at all. Shared pipes in HDB estates are normally handled by the Town Council, and in condominiums by the management office. Check your Town Council or management office notices for an after-hours contact number.

For water coming through the ceiling from the flat above, HDB's ceiling-leak guidance explains how ceiling leaks in flats are handled. Contain the water, speak to your neighbour and follow that process before booking your own repair.

What to ask an after-hours plumber

If you decide you need someone tonight, a few questions on the phone can prevent surprises when the bill arrives.

• Is there a call-out or after-hours charge, and is it separate from the repair?
• Does the price change after a certain time or on public holidays?
• What does the inspection fee cover, and is it deducted if you go ahead with the repair?
• Can they give a price for the likely repair before starting, and will they ask before doing any extra work?
• Are common parts carried in the van, or will a second visit be needed?
• Who will do the work, and is the job one that needs a licensed plumber?

PUB's requirements for plumbing works explain which water-supply work must be done by a licensed plumber. The licensed plumber guide explains how to check a plumber's details and what to ask.

Questions

Where is the main water valve in an HDB flat?

In many flats it is near the water meter, often in a service duct, the corridor or near the kitchen. Locate it and try it before you need it, so you know which way it turns and whether it is stiff.

Should I call a plumber at night or wait until morning?

If closing a valve stops the leak and the area is safe, waiting for a daytime visit is often fine. Call tonight if you cannot stop the water, if it is reaching electrical points or if you cannot isolate the leaking pipe.

What if the leak comes from a corridor pipe or the ceiling?

The source may be a shared pipe or the unit above. Contact your Town Council or management office, using any after-hours number on their notices, and follow HDB's ceiling-leak process for water from the flat above.