Flood Risk Facts

Flood Risk Facts2021-02-12T19:16:26+00:00

Cavity Wall Insulation, Flood Risk Facts, Flood Risk Home, Defects Investigations.

For 6.3 million families in the United Kingdom, risk of flooding is a fact of life.

Flooding is the most common and widespread natural disaster in the UK, the annual cost of flood damage in England alone is more than £1.1bn and is expected to rise, so it’s important that homeowners and businesses should be properly informed of the potential risks of flood damage to their property.

Fig 1. Flood Risk Homes

For over a decade there has been at least one serious flood a year in the UK, and experts are now predicting the impacts of climate change and rising sea levels could increase the intensity and frequency of inland, coastal, and flash floods over the coming years.

Insurers are warning that increased flood risk could push up the cost of premiums for everyone, while also leading to higher excess for all those businesses and households unfortunate enough to have to claim for flood damage.

For Homeowners

Published data by the Building Research Establishment (BRE) confirms the outer leaf of any masonry cavity wall construction is not watertight. Water will inevitably penetrate the outer leaf of unprotected cavity walls.

The Building Research Establishment publication, BRE Good Building Guide 44: part 2: “Insulating masonry cavity walls – principal risks and guidance” states,

There can be an increased risk of rain penetration if a cavity is fully filled with insulation, ie moisture is able to transfer from the outer to the inner leaves resulting in areas of dampness on internal finishes.

Rainwater, under certain driving rain conditions, can penetrate the outer leaf of masonry leading to wetting of the standard cavity insulation, a reduced thermal performance and damage to internal finishes.”

Fig 2. CWI Flood Damage to electrics

Therefore, great care is required in the selection of cavity wall insulation for use in homes in flood risk areas as flood waters will be in direct contact with insulated walls and subject the insulation measure to much greater hydrostatic pressures that can buckle walls and cause major damage to cavity wall ties, standard (fibre, bead) cavity wall insulation materials, plaster, electrical appliances, furnishings and decorations.

How Homes and Businesses Can Reduce Rising Flood Costs

The escalating risks and costs associated with floods are leading to increased calls for businesses to take action to reduce the impact of flood and ensure they have taken steps to limit damage when floods occur.

The Environment Agency are advising all businesses operating in areas at risk from flooding that they should have a response plan, arguing that following simple best practices could lead to savings of 20-90 per cent in the cost of lost stock and equipment in the event of a flood.

“Flooding is the most common and widespread natural disaster in the UK, so it important for businesses to pay special attention to it,” says Simon Hildon, Environment Agency senior flood risk adviser.

To check if your home or business is at high risk of flooding from rivers and sea, reservoirs, go online to the Environment Agency’s interactive mapping service, which also provides information on which areas currently face flood warnings.

If your business is located in an area of high flood risk you can also sign up for a 24/7 flood alert service called Floodline Warnings Direct, which gives you instant access to the latest flood risk updates.

Some Advantages of incorporating flood resilient (FRe) materials in place of standard materials

  • Avoids incorporating materials which absorb or retain water for prolonged periods after flooding

  • Retain their physical integrity and have low moisture take up when exposed to flood waters

  • Remain serviceable after the flood water recedes

  • Avoids repeat costs associated with extraction, removal and drying out of materials which can be exorbitant, highly disruptive and cause unsightly damage to the external appearance of the property.

  • Can reduce high costs associated with temporary accommodation.

  • Quick pay back, not only saves on heating bills throughout the life of the building but also saves costs associated with each flood incident

  • Reduce risk of mould

  • Reduce risk of wet rot

  • Can be used in combination with other flood resilient measures as part of a whole house flood resilient system

  • May reduce insurance premiums.

For details of Standards for materials and products that relate to construction and flood resilience go to www.floodguidance.co.uk/flood-guidance standards

If you have had cavity wall insulation (CWI) carried out on your home which has caused damp, black mould, or health related issues, etc, and you require the assistance of a chartered building engineer please click here to contact us.