Water leak at home: what to do while you wait for the plumber

A water leak never gives you a warning. Before I arrive, a few simple steps will limit the damage in your home and your neighbours'. Here, in order, is what I tell my customers on the phone.

1. Shut off the water

This is the most important step. If the leak comes from an appliance (toilet, washbasin, washing machine), first close the small valve that feeds it, usually just behind or underneath.

If you can't find the source, close the main stopcock. In a house, it is usually near the water meter. In an apartment, look under the kitchen sink, in a utility cupboard or in the service shaft on the landing.

Then open a low tap (sink or bath) to drain the water left in the pipes: the leak will stop sooner.

2. Make the electrics safe

If water is running near a socket, a light fitting or the fuse box, switch off the power at the main breaker. Don't touch a wet electrical appliance. If the water heater is leaking, switch off its breaker too.

3. Limit the damage

Mop up, put buckets under the drips and move furniture, rugs and appliances out of the way. If water is coming through the ceiling, don't stand underneath: a soaked ceiling can give way.

4. Take photos

Photograph the leak, the water marks and anything damaged before you clean up or throw anything away. Your insurer will ask for them.

5. Alert your neighbours and the building manager

In an apartment, water travels. If it is coming from the ceiling, go and see the neighbour upstairs. If they are away, contact the caretaker or the building manager (the syndic). If the leak comes from a shared pipe, it is the syndic who calls out the plumber.

Warn the neighbour below as well: better they hear it from you than from a stain on their ceiling.

What if you can't see where the water is coming from?

A spreading stain on the ceiling, a damp smell or a rising water bill can point to a hidden leak. A simple test: close every tap, note the numbers on the water meter, then use no water for one or two hours. If the numbers have moved, there is a leak somewhere.

There's no need to break into a wall at random. For leak detection, I use acoustic detection, a thermal camera, tracer gas and video inspection of the pipes. I then give you a written report, with photos, to send to your insurer.

Insurance

Report the water damage to your insurer as soon as possible: in France the deadline is usually 5 working days, but check your policy. If a neighbour is affected, fill in a joint water damage report together (the constat amiable dégât des eaux). Keep all invoices and the leak detection report.

What to avoid

Don't attempt a DIY repair on a pipe under pressure, don't let the water run "in the meantime", and don't switch the power back on until everything is dry. Tape or sealant can hold for a few hours, but it is no substitute for a proper repair.