Disaster Advice
Disaster Advice Disaster Advice
Disaster Advice Disaster Advice Disaster Advice
Disaster Advice
Disaster Advice
Water Damage

Need expert help?  (email) or call 08700 789 999

Water is known as the universal solvent for very good reasons; it can dissolve granite and steel. Water, is essential for all life forms to exist and where water has escaped in a building it has the ability to corrode and magnify existing life forms such as mould and bacteria. It can and cause various other damaging effects ranging from cracking and swelling of wood products to short circuits in electrical components. Initial water damage is called primary damage and the effects are usually instantly identifiable, what is harder to see is the secondary damage as the moisture changes form from liquid to vapour or gas phase and travels throughout the building causing secondary damage as it reforms in condensation to be adsorbed into porous materials, creating damage that could have been prevented.

Water Travel characteristics

  • Water can travel vertically or horizontally and it‘s escape route may affect unexpected areas which may require detailed evaluation or identification utilising measuring equipment. Where the water has entered a building from an outside source it can be expected to carry various contaminates and health threats, including heart disease, hepatitis, and various gut infections including E.coli 157.The IICRC Americas, Institute of Inspection Cleaning and Restoration Cleaning has identified over 1500 bacterial and 120 viral infections possible in flood waters. These health hazards are amplified by the possible formation and growth of mould, some of which may be toxigenic.

Damage Types

Primary Damage

  • The initial results of water damage include swelling, shrinkage and colour transfer, all of which are usually irreversible.

Secondary Damage

  • Secondary damage is the subsequent effects and are often preventable. Typically, the effects of rising relative humidity caused by heating and evaporation, or simply moisture travelling to areas previously unaffected.
  • Water is known as the universal solvent and can travel in liquid, gas and vapour phases, capable of transmitting through solid concrete in its gas phase.

Water damage is classified in three categories.     (From IICRC S500)

  • Clean, an internal leak from a burst pipe.
  • Grey, an internal leak containing some contaminants, typically a washing machine overspill or broken toilet bowl, but no solids or backflow.
  • Black, almost any water from an outside source, travelling over or through soil, covering sea and river water, and sewage. Typically this type of water can contain 120 viral and up to 1500 bacterial infections. Of special concern would be those individuals with immune suppressive systems, including diabetics, long term prescription drug users, those on cortisone. Children under two may not have a developed immune system and those over 50-60 may have a depleted system.
  • In water damage, cleaning is of paramount importance followed by sanitation and drying.
  • Drying is completed when the moisture content of affected areas match the moisture content of unaffected or estimated pre-loss conditions.

Damage Advice

  • New legislation introduced to protect homebuyers now requires vendors to disclose any flood or damage event to a home over the past three years. This may affect the value of your home or building if you cannot prove correct remediation. (Click here)
  • Following a water damage incident a risk and hazard assessment must be made. This is simply assessing if you could be harmed, i.e.: electrocuted or face other health hazards such as biological contamination. If in doubt get professional help.
  • Make sure the leak or source of water intrusion has been stopped.
  • Unlike flood damage water damage is usually an isolated area and event. The main priority is to prevent the water migrating or causing secondary or unnecessary damage to areas previous;ly unaffected.
  • When you stop secondary damage its called mitigation and you may be required to mitigate damage under the terms of your insurance policy. Always take notes, photos where possible and document all damage and disposable items. Time is your most valuable asset in post disaster scene; use it wisely by identifying cost benefit issues. Typically time spent saving a £100 computer game would be wasted if you could have spent it saving a £200 radio, this is called triage.


  • Identify urgent actions in priority of value.
  • Lift furniture off floor to avoid wood stains affecting the carpet.
  • Pin up drapes and furniture skirts to prevent staining or wicking.
  • Place plastic or tin foil over or under furniture feet to prevent absorption of water resulting in cracking and swelling.
  • Pull back carpet to identify potential damage and seepage.
  • Install drying programme.
  • Consider mould, bacteria, odour and sanitation as direct result of inadequate or slow drying programme.

Contents and Structure


  • Carpets can usually be salvaged if controls are installed promptly. Under felt (pad) too can be salvaged although the risk/benefit may make replacement a better option. Remeber that rubber backed carpet ,floor tiles and vinyl are moisture barriers and may prevent the floor drying, so removal or floating may be an option.Where black or dirty water is involved, cleaning may not remove all contaminates and health hazards may remain, disposal may be the only viable option. Wood flooring, laminates and tiles can be salvaged but may need sub floor ventilation and specialist assistance. Remove skirting and cork swell strip where fitted. Natural wood isusually salavageable although many cheaper laminate floor systems are based on MDF or reconstituted wood which is unlikely to survive any but the smallest exposure to water.


  • Solid or cavity walls may respond to air injection. Similarly stud or plasterboard walls can be injected with dry air to facilitate drying and reduce disruption and removal.

Water Damage

  • Various forms of damage can require different restoration techniques. Water damage has been classified can be divided into three categories by the IICRC in their guide document S500:-

  • Blackwater floods generally require disposal of affected soft or absorbent materials such as carpets, upholstery, toys, beds etc. This is because economical sanitation is not practical. Kitchen cabinets, furniture generally made from chipboard will swell and loose shape, split at joints and loose its strength, requiring replacement.
  • Never dispose of anything before your loss adjuster/insurers says it‘s alright to do so.
  • Contents from grey and clear water floods can usually be salvaged if works and controls are quickly put into place. Where this is not achieved the category 1 and two can escalate to a class 3 incident as bio amplification occurs over time.

Sanitation/ Water Damage

Despite the claim of many advertisers disinfectants are not nearly as beneficial as you might imagine. In fact many food poisoning outbreaks occur after a kitchen clean. Almost all disinfectants are neutralised by dirt, i.e. dirt can stop the disinfectant working.

The only way to sanitise is: Clean

When you use a contractor to restore flood damage you should be confident that they are competent and skilled in restorative drying and sanitation prior to any refurbishment works. Condensation on windows is a clear indication that the dehumidification program installed is inadequate. Too much heat can cause uncontrolled evaporation and although the building looks like its drying the moisture may simply travel from wet areas and be absorbed into previously dry materials. Drying quickly is very important, where buildings are left wet in an uncontrolled state for several days, mould may form which may cause adverse health effects. (See mould section)
Typically most common problems arise when rebuilding or renovation is improperly dried or sanitised.

Consequences include:-

  • Musty Odour
  • Visible Mould
  • Rot
  • Condensation on windows
  • Wallpaper peeling
  • Efflorescence - white or crystal salts found on the wall
  • Flooring buckling
  • Floor tiles lifting at edges
  • Cracks
  • Doors stickingThese effects are consequences of poor restoration by contractors and can result in costly remediation, which may not be recoverable from your insurers. You may have to carry the cost if your builder or restoration contractor is not insured or willing or able to resolve. Mortgage lenders, surveyors and the residual value of your home may all suffer adverse effects from these issues, i.e. reduce the value of your property.

  • Your insurer should pay for the professional restoration of your home and/or business after flood damage. If procedures or monitoring are unsatisfactory, damage to your structure or contents is possible. Typically mould, rot and condensation can result in loss or damage which as a subsequence of poor workmanship may not be recoverable from insurers. If you suspect the contractor you are using is not competent, talk to them or your insurer. A plan of work, expected results and estimated time frame should be provided. Even after work has been completed you may have redress for latent or hidden sub standard work for a period upto 20 years after the event !

Latent Damage

  • After a flood or water damage, some water damage may be difficult to see or may manifest later as latent damage. It is of course essential to ensure that the building is dry and sanitised before renovation is undertaken.
  • You may need special equipment to measure moisture content and professional help may be your best route especially where you have doubts.
  • If it goes wrong and buildings haven‘t been dried or sanitised properly, the following indicators may be useful:


  • Bad odour - This may be caused by either flourishing bacteria or mould.
  • Sore eyes, running nose and general flu like symptoms - Possible hidden mould or bacteria reservoirs, under floors, in cavity walls etc.
  • Condensation and still wet - Misting windows, wallpaper peeling or gaps, skirting board gaps.
  • Mould is generally allergenic and may develop in hidden areas such as cavity walls etc.
    Useful information


  • The engineering controls required to safeguard a home from the effects of flood water are extremely complex and may be very expensive if professionally installed. Typically sand bags properly installed may prevent some water getting in but water in flood scenes will often travel under ground and get into a building through, air bricks, service holes for pipes, cables etc. It can even just migrate up through the floor.
  • If you live on a flood plain it may make some sense to make some assessments about professional protection, this may take the form of raised barriers or non return valves fitted to toilets and internal drains.
  • The total sealing of sub base may be a consideration but the reality is that unless flooding is a regular occurrence, the engineering controls may be more effective in preventing damage to internal finishes, structure and contents.
Remember that sand bags are only effective if installed properly, typically they should be staggered, just like a brick wall, they can leak, so where practical place plastic sheeting, (you can get this from builders merchants) on the floor before you build and cover the threatened face by pulling the sheet up and over the top. The last row of sand bags are then placed over the sheeting to hold it in place.Nerw types of defence are now available and you should call us for more information.

You should be aware that where floodwater height is 1 metre the pressure on a building may be as much as 1 ton per square metre, this may result in building movement and sometimes it may be safer to allow the water into the property to allow pressure equalisation.

You can get more information from the following sources.

Association of British Insurers
National Flood Forum http://www.floodforum.org.uk/

Flood Advice

Initial Response

  • Health and safety assessments
  • Triage assessments
  • Remove standing water
  • Triage action
  • Clean Sanitise
  • Dry and dehumidify
  • Multi clean and sanitise

Health and safety

  • Following any disaster there is a need to assess where or if danger or hazard may exist. This is accompanied by risk assessment, which is the possibility or probability of that hazard harming you or others. Typically in a flood electrical safety, germs and sanitation may represent significant hazards with slipping another concern. The deep-seated contamination not visible should also be considered. This may be in the walls, cavities, and electrical appliances such as fridge and freezer walls or insulation.See our Health & safety section.

Remove standing water

  • This is quite simply the pump out or wet vacuuming the floors or basements to remove any free water.

Triage action

  • The action following the earlier assessments. This may be as simple as removing damaged paintings or computers from getting worse, or the raising of wooden table legs off wet floors to prevent swelling.

Clean and Sanitise

  • Quite simply the preferred method of sanitation, cleaning and source removal results in sanitation but additional use of antimicrobilas may be advised.See multi clean operation.

Dry and Dehumidify

  • The installation of a balanced drying program to maximise evaporation and moisture release against the collection of the evaporation. Where evaporation quantity exceeds that of the collection method, and dehumidifier for example, secondary damage may result as the uncollected evaporation moves into previously dry substrates or surfaces.

Multi Clean and Sanitise

  • As the surfaces begin to dry out they may bring further contamination to the surface, which may then require additional cleaning and sanitation.

Disposal or Restoration.

  • Soft furnishings, carpets and beds are unlikely to be salvaged after being submerged in a flood, but photo‘s I.T. or electrical circuitry may, subject to professional salvage techniques. Any items identified as unsalvageable should be listed, photographed if possible and kept for inspection by your insurance company or their agent the loss adjuster. Do not dispose of anything unless authorised or a health risk is considered.

Restoration Procedure

  • As the water subsides silt will be left. Where practical either shovel or hose of this residue. Apply a 5% household bleach solution, that‘s 1 bottle of bleach to 9 bottles of water. Remember sanitation follows cleaning.

Electrical Safety

  • Turn of your electricity. Do not do this whilst standing in the water. Use a wooden tool of some kind. Even if you know that the power is down in the area, make sure yours is off in case it comes on suddenly when the power returns to your area.
  • When water is escaping and running away it will find any hole to run through - electrical sockets and lights provide excellent escape holes. Generally speaking if your electrical system is well maintained there is no reason why, when completely dry, it should not still be fine. We suggest however, that it is worth peace of mind to put checks on everything, such as - taking front covers off plug sockets to check for water and checking your central heating boiler for damage. Use accredited electricians and Corgi gas fitters.
  • Wait until the water has subsided and then call your electrician – they cannot do anything while some of the system is under water. Remember - you will need to use a generator, to power cleaning equipment until this is done.

Safety and Hygiene

  • Your appliances such as fridge, freezer, ovens etc with foam insulation and sealed components will suffer little visible water damage, however, once again do not attempt to use them until fully dried out and checked by your electrician whilst he is doing your general check. However, any electric motors that have been under water will need to be either reconditioned or renewed. Any food that was in them when the flood hit should be discarded because of the dirty water and the risk of contamination. Insulation in fridge and freezers may be contaminated and sanitation is impractical or uneconomic.

Gas Safety

  • If you smell gas or have reason to suspect a leak, turn the gas off at the mains. Call the emergency gas services and do not attempt to use any gas appliances.
    Your central heating boiler must be checked over by either an NICEIC (electric) or CORGI (gas) registered engineer. Parts such as the burners and thermostat may need to be replaced. Indeed it may be cheaper to renew the whole thing anyway.Of special consideration is the gas jets which may in deep floods become clogged with silt and if not properly cleaned result in partial combustion, soots, carbon monoxide poisoning.


  • This assessment is a guide only and meant to assist. You should always use competent people to undertake dangerous tasks and they should provide a professional risk assessment.
    Action: Turn off electricity to flooded building.

What are the hazards?

  • Slimes and silt will make the floor very slippery. Floorboards, lino and carpet may have swollen and caused a hidden trip hazard. Biological contamination will probably be present, wear gloves. Please refer to our information regarding Personal Protective Equipment.


  • The electricity may still be on despite the house being in darkness. Your building, especially if older, may not have been wired safely! Earth wires may not have been fitted and electrocution is a risk. Walls are sometimes live. Make sure you wear rubber soled shoes or boots, put one hand behind your back, this would give you some protection against electric shock across your heart. Enter the building in daylight if possible. Use dry plastic or wood to operate switches or handles, (one hand only) isolate at fuse board. If water is above fuse board do not enter building unless you know main power is off. Do not turn on any electrical equipment (often it has been affected by water damage) until it has been professionally tested and certified. Remember that if you live in a terraced or semi detached home your neighbour’s electricity may be on and live in a party wall.
  • You may find that floors have swollen, plaster becomes live and after a few days a bad odour develops.
  • Swelling floor boards and skirting should be lifted or removed. Sub floor areas should be cleaned where possible to remove silt and contaminants. Professional help may be necessary to remediate sub floors.
  • Cavity walls also may require inspection but institu drying may be possible by professional contractors. Remember if your building is a grade I, II or III listed building you are not allowed to dismantle or damage any of it without permission from English Heritage.
  • Although your electricity supply, may be isolated your neighbours in attached property may still be live and the risk of electrocution may exist.

Drying Out

  • Generally after a major flood the inside of a property will be wetter than the outside. Open all windows and doors to encourage air flow and dilution of odour. Be careful when using heat to dry buildings as the uncontrolled evaporation may rise and condense in previously unaffected areas causing unnecessary secondary damage. Use dehumidifiers properly.
  • Furniture made of solid wood may be salvageable, but chipboard and MDF may not survive as it may swell and distort. This may lead to the loss of integrity or strength. If you are insured you should contact your insurer as soon as possible but remember you have a duty to mitigate or control damage where you can. The use or recruitment of professional assistance is usually covered by your insurance policy.
  • Plaster may be salvageable but wall covering must be removed. Following sanitation and drying out a health check for contaminants may be prudent.
  • Remember that new conveyance forms may specifically request information on flood events and request proof that restoration was undertaken and completed professionally and may require certification or proof.

Drying Problems

  • Almost all drying procedures install dehumidifiers in a room where they pull moisture from the air. The air absorbs the moisture from the wet surfaces after it has evaporated from the wet surfaces, walls floors etc. This means the areas you want to dry first are the last to dry as the effect is to draw water inwards making the flow from out to in. The common sense approach may be to reverse this by the use of controlled heat and ventilation.
  • Concrete floors in particular may hold moisture for months unless special procedures are undertaken to encourage water removal. This may require vacuum pumps, not wet vacs, air movement or forced ventilation with controls. Concrete can take up to a month per inch of thickness to dry and it maybe imperative to identify “DRY” before floor coverings are reapplied to prevent damage or mould.
    Cavity walls and stud or plasterboards walls in particular can present difficulties in drying and inspection can be required into cavities to ensure drying programs have been completed properly.
    Mould and rot issues are obviously key factors where poor drying regimes have been undertaken.
See other sections too,
  Disaster Advice
Disaster Advice
Disaster Advice Sections
Disaster Advice
Disaster Advice

Disaster Advice

Disaster Advice

Disaster Advice
Disaster Advice
Disaster Advice Disaster Advice Disaster Advice
Disaster Advice Disaster Advice