PanicStation.org
UK USA
uk Home & property emergencies

What to do if…
you find water collecting under a tiled floor and suspect a leak beneath the tiles

Produced and maintained by PanicStation.org Published: Last reviewed: Editorial policy UK guide

Short answer

Turn off the water at the internal stop tap if you can do it safely, keep people off the wet tiled area, and avoid touching electrics near the water. Then arrange urgent plumbing help and report it to your landlord or building manager if relevant.

Do not do these things

  • Do not keep using taps, showers, toilets, washing machines, or dishwashers to see whether it stops.
  • Do not switch on underfloor heating or try to dry the floor by heating it.
  • Do not pull up tiles, chisel grout, or cut into the floor while the leak may still be active.
  • Do not use plug-in heaters, extension leads, or mains-powered dehumidifiers on or near the wet area.
  • Do not touch switches, sockets, appliances, underfloor heating controls, or the consumer unit while standing on a wet floor.
  • Do not step into standing water if it may be near sockets, appliances, wiring, or underfloor heating electrics.

What to do now

  1. Make the area safer. Keep children and pets away. If tiles feel loose, raised, cracked, or spongy, treat the area as a slip and trip hazard.

  2. Turn off the water supply. Find the internal stop tap, often under the kitchen sink, in a utility area, hallway cupboard, downstairs toilet, or near where the mains pipe enters. Turn it clockwise until it stops, then briefly open a cold tap to check whether the flow slows or stops.

  3. If water keeps appearing after the stop tap is off, escalate it. Contact an emergency plumber. If you think the water may be coming from outside your home, a shared supply, or a pipe you cannot isolate, contact your water company or water provider as well.

  4. Avoid electrical contact. If water may have reached sockets, wiring, appliances, the consumer unit, or underfloor heating electrics, stay clear of the affected area. If you can reach the consumer unit from a dry, safe position, and it does not look wet, hot, damaged, buzzing, or arcing, switch off the affected circuit or the main switch. If you cannot do that safely, leave it alone and get professional help.

  5. Use the right emergency route for electrical danger. If someone is in immediate danger, call 999. For electricity network danger or a power cut in Great Britain, call 105. In Northern Ireland, contact NIE Networks on 03457 643 643.

  6. Stop any obvious appliance source if it is dry and safe to reach. If the leak may be from a washing machine, dishwasher, fridge water feed, toilet feed, or shower pump, close the local isolation valve only if you can do it without stepping into water or touching wet electrics.

  7. Limit spread without disturbing the floor. Wipe up surface water if it is safe. Use towels, trays, or buckets where water is emerging. Do not lift tiles or dig into the floor before the water is isolated and a plumber has advised.

  8. Record the visible damage. Take quick photos or video of the wet area, grout lines, lifting tiles, nearby skirting, walls, ceilings below, and any appliance connections. This can help a plumber, landlord, building manager, or insurer understand what changed.

  9. Tell the right person urgently. If you rent, report it as an urgent repair and say that water is collecting under a tiled floor, whether you have turned off the water, and whether electrics may be affected. If you are in a flat or shared building, tell the building manager, concierge, freeholder, factor, or managing agent because water can affect other homes and there may be shared shut-off points.

What can wait

  • You do not need to decide now whether tiles, flooring, plaster, or decoration need replacing.
  • You do not need to settle blame, insurance responsibility, service-charge responsibility, or landlord responsibility while water may still be spreading.
  • You do not need to lift tiles to prove where the leak is before the water is off and the area is electrically safe.
  • You do not need to choose a permanent repair today if the immediate leak is still being isolated.

Important reassurance

A hidden leak under tiles can feel frightening because the source is out of sight. The most protective first steps are simple: keep away from wet electrics, stop the water if you can, limit spread, and get urgent help.

Scope note

These are first steps only. Finding the exact source, such as pipework, a waste pipe, a shower tray, failed grout, appliance feed, or underfloor heating loop, may need a plumber, leak detection specialist, electrician, landlord, building manager, or insurer.

Important note

This is general emergency guidance, not legal, financial, electrical, plumbing, insurance, tenancy, or professional advice. If you cannot safely isolate water or electricity, or you think electrics are involved, keep clear and contact appropriate emergency help or qualified professionals.

Additional Resources

Closely connected guides that may be useful during the same situation or its immediate aftermath.

About this guide

This guide was produced and is maintained by PanicStation.org using its published editorial process. Official and specialist sources are checked where relevant, and AI-assisted tools may be used for drafting, organisation, and consistency checks. The site operator remains responsible for publication, revision, and removal decisions.

Support us