Water Leak Advice for Flats

A quarter of all insurance claims made on flats are for damage caused by water leaks. The damage costs millions of pounds and causes heartache to those involved and disputes between neighbours over who should pay.

Preventing Water Leaks in Flats

Bathrooms & Toilets

  • Check the condition of all your seals. These are the white flexible beads that run around your bath and shower, allowing water to run from your tiles and back into the bath/ shower. If the mastic seal is damaged, split, lose or curling away from the wall or bath, water can freely run down the back of your bath or shower, and eventually make its way through the ceiling and into the property below, often through a light fitting.
  • Check the grout in a bathroom (between the tiles) especially around wet area. Gaps in grout can allow water in behind tiles, causing damp patches, risk of water leaking into the property below and other rooms, and tiles coming loose.
  • Toilets also need to be checked. If you hear any irregular sounds, such as the flush cycle taking longer than it normally does, or humming sounds, it’s a good idea to have it checked over, and is often remedied by adjusting the valve or replacing the inlet valve washer.
  • You may inadvertently be causing damage to the exterior of the building if your toilet is making a constant running sound. This will mean the external overflow is allowing water to escape onto walkways below and in icy conditions you could be causing a hazard. It will also mean staining to walls, encourage vegetative growth, damage mortars, and lead to possible ingress elsewhere.
  • Check taps for drips (often repaired by replacing a washer) and humming or vibration sounds when using the taps.

Ensure that if you have a service duct or main stack within your property, it is accessible. The duct may provide access to valves, all main services, rodding eye and in some flats, you will share these services with your neighbouring flat.


  • Check your seals at the back of your kitchen worktop and around your sink. Spills need containing and gaps can often cause water to penetrate down the back or into your units.
  • Check your plumbing. Normally under the sink is where everything comes together – your water outlets for your dishwasher and washing machine, your isolation valves, and the waste from your sink etc. Make sure that nothing is leaking, and the outlet connections from your washing machine/dishwasher are secured and in place; frequent vibrations can cause these to become loose. Also check your plughole is not leaking.
  • If you have a washing machine carry out frequent checks on the hose as this is a major cause of leaks.
  • Check taps for drips (often repaired by replacing a washer) and humming or vibration sounds when using the taps.
  • If you have a service duct within your kitchen please ensure that this is fully accessible in the event of an emergency.


  • Check your radiators, valves and exposed pipe work for leaks and any signs of corrosion and rust.
  • It is important that you carry out regular checking/monitoring of all radiators/pipework within your flat where visible.
  • Leaking radiators must be fixed. The damage to flooring, carpets and floorboards could be a lot more serious and expensive than you might think.

Stop taps and devices to reduce water damage

Do you know where the stop tap for your flat is located?

Can you easily turn it or is it rusted? Being able to turn off the water supply easily if water is leaking could save you thousands of pounds of damage and insurance premiums.

An annual test of the stop tap is a good exercise.

It is good preventative maintenance to spray WD40 or similar around the stop cock. And make sure your family members also know the location of the stop cock.

There are devices on the market that can be installed by leaseholders to reduce the likelihood of prolonged water damage. One device is a switch, like an electric socket switch, which will turn off the water supply at the stopcock.

What can you do to help your managing agent if a water leak does occur?

Make sure your residential managing agent has up-to-date contact details for you or your letting agent or tenant in case no one is at home. This way it is easy for you to be contacted if you have a leak which is resulting in damage to a neighbouring property which will help to minimise damage.

Buildings insurance and water damage

In the unfortunate event of being affected by a water leak you should submit a claim to the building insurers and your own contents insurers.

Electrical safety and general advice for homes affected by water damage and flooding

  • Make sure the property is safe before you enter
  • Try to avoid direct contact with any water which remains. It may be contaminated
  • Have a torch at hand when entering the property
  • Switch off the electricity supply at the fuse box if it is safe to do so. If there is evidence of water inside the fuse box stop and seek professional advice
  • Unplug damaged electrical appliances and move all portable ones away from the area affected by flooding
  • Arrange for other services, such as gas, to be switched off. Electricity and gas supplies should not be turned back on until you have had professional advice that it is safe to do so.

Do not attempt any electrical repairs or connection of temporary supplies yourself – always use a registered electrician:

  • Arrange for a periodic inspection and test to be carried out on the property. The registered electrician will issue you with an Electrical Installation Condition Report (EICR) which will identify the condition of the wiring and equipment in need of repair
  • All the portable appliances affected by the flood will need to be tested to make sure that they are safe for continued use
  • Fixed equipment, such as electric cookers, storage heaters, boilers etc. should also be tested
  • If the water damage to electrics is relatively minor and caused by clean water, i.e., a burst water pipe or tank, then it is likely that the registered electrician will just need to dry out cables and replace any accessories affected by the water (sockets, switches, plugs etc.)
  • If there is major flood damage to the electrics caused by clean or contaminated water, then it is likely that parts of the electrical installation will need to be rewired. When rewiring is necessary, ask the registered electrician about the possibility of raising the height of the newly installed electrical equipment, including raising the fuse box and sockets to above any future expected flood level.


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