Britain's biggest insurer has warned that more than 100,000 new homes due to be built across England over the coming decade could prove impossible to insure, because they are being placed in areas increasingly exposed to flooding.
Dame Amanda Blanc, group chief executive of Aviva, said the threat from flooding was 'absolutely increasing', and that on current building patterns roughly 115,000 new homes would be constructed in flood zones over the next decade. 'That doesn't seem to me to make sense. We need to think about where those homes are being built,' she said in an interview released this week on the BBC's Big Boss Interview podcast.
Pressed on whether England was putting up properties that might one day prove uninsurable, Blanc said it was doing so 'for sure', and argued that the danger areas were already well mapped. 'It's very well known where these flooding areas are. Let's think very carefully about homes that are being built.'
Why New Builds Fall Outside the Safety Net
New homes in flood-risk areas also fall outside the scheme that keeps flood cover affordable for most households. Flood Re, the industry-backed reinsurance arrangement launched in 2016, allows households in high-risk areas to obtain affordable policies, but it excludes any home built after 1 January 2009, a cut-off designed to deter building on exposed land. The scheme is itself due to wind down in 2039, after which the market is expected to return to fully risk-reflective pricing, leaving the newest homes in flood-prone areas with no Flood Re protection at any point.
Aviva's analysis found that one in nine homes completed in England between 2022 and 2024 stood in areas of medium or high flood risk, up from around one in 13 in the preceding decade. Blanc's projection assumes that pace holds. About 110,000 new homes have already gone up in the flood areas over the past 10 years, and Aviva expects a further 115,000 to follow over the next decade if the trend continues.
Millions of Properties Already Exposed
About 6.3M homes and businesses in England are already at risk of flooding, according to the Environment Agency, a figure it expects to climb to around 8M, or one in four properties, by the middle of the century as the climate warms.
Aviva's Building Future Communities report, published in October 2025, projected that every constituency in Great Britain would see rising flood risk from rivers, the coast, or surface water. In England, 69 per cent of constituencies are forecast to record a rise of more than a quarter in the number of properties exposed to flooding by the 2050s. Greater London and Essex account for the largest concentrations of at-risk new homes, with parts of south London among the areas where the greatest share of properties could be threatened by 2050.
Aviva Presses for Tougher Planning Rules
Jason Storah, chief executive of Aviva's UK and Ireland general insurance business, said the insurer supported the government's drive to build more homes but wanted the planning rules tightened. He warned that developments in flood zones could also raise the risk to existing homes nearby, and called for a presumption against building in high-risk areas, backed by mandatory flood-resilience standards in building regulations.
'In some areas, it will not be a case of if, but when, a home will flood,' Storah said. Tougher rules, he argued, were essential to keep properties insurable and to protect their value, adding that building the homes the country needs and steering them towards lower-risk land were 'not mutually exclusive objectives.'
Government Rejects 'Misleading' Figures
In February, the government rejected the thrust of the analysis. The Ministry of Housing, Communities and Local Government said some of the figures were misleading because they did not account for existing flood defences, such as the Thames Barrier that shields much of central London. It added that 99 per cent of proposed new homes in planning applications in 2024/25 complied with Environment Agency advice on flood risk.
Ministers have pledged to deliver 1.5M new homes 'without compromising on safety,' pointing to a record £10.5B ($13.9B) programme of flood defence works intended to better protect nearly 900,000 properties by 2036.
