One in nine new homes built in England between 2022 and 2024 was constructed in areas at medium or high risk of flooding, according to new analysis by Aviva, raising fresh questions for insurers over future affordability and insurability.
Using Ordnance Survey address data for 396,602 new homes and the Environmental Agency's flood maps at constituency level, Aviva found that 11%, or 43,937, of new properties are already in medium or high flood-risk areas, while 26%, or 101,657, have some level of flood risk.
That marks a sharp rise from Aviva's previous analysis, which found that 8% of new homes built between 2013 and 2022 were in flood risk zones. Comparable government figures have not been published since 2022, but the new study suggested that as housebuilding has accelerated, so too has construction in higher-risk locations.
Looking ahead, Aviva projects that, by 2050, one in seven of the new homes built between 2022 and 2024 will be at medium or high flood risk, and almost a third will face some level of flood risk, compared with around one in four existing homes.
The findings come against a backdrop of rising weather‑related claims. Deloitte has estimated that UK insurers will have paid around £1.6 billion in weather‑related property claims for 2025, up from £1.3 billion in 2024 and more than double annual levels seen between 2017 and 2021.
Jason Storah, CEO UK & Ireland General Insurance at Aviva, said the insurer backs the government’s ambition to build more homes and is itself a major domestic investor, with a £25 billion commitment over the next decade. He argued, however, that volume targets needed to be matched with decisions about siting and resilience.
Storah said Aviva’s analysis showed “too many new homes” being built in higher‑risk areas and that it was “particularly worrying” to see this trend intensify as housebuilding picked up. He also highlighted that these properties fall outside the Flood Re reinsurance scheme, which excludes homes built after Jan. 1, 2009, in an effort to avoid incentivising development in floodplains.
Aviva's earlier consumer research also suggested that the exposure is not just theoretical. More than half, or 58%, of owners of homes built between 2019 and 2024 said their property had already been affected by a weather-related event, and about 22% reported flooding, almost double the rate for all residents.
The analysis also indicated that almost a third of constituencies with the highest numbers of at-risk new homes are in Greater London and Essex, with further concentrations in Lincolnshire, the North West and western regions.
Those patterns align with wider investigations which have found that London and parts of eastern England dominate the constituencies projected to have the highest proportions of homes at risk from river and coastal flooding by mid-century.
Planning policy in England is supposed to apply a “sequential, risk‑based approach”, steering new development to areas of lowest flood risk and only allowing building in higher‑risk zones where there are no reasonable alternatives. Recent media reports, however, have highlighted approvals for schemes in high‑risk areas, suggesting the system is under strain as ministers push to deliver housing targets.
Storah warned that new developments in flood zones can also alter drainage patterns and increase the likelihood of flooding for existing homes nearby if resilience measures are not embedded.
Separate analysis has suggested that current flood damage costs the UK around £1.3 billion a year, with low‑income households disproportionately exposed and often uninsured.
A 2025 review led by former Environment Agency chair Emma Howard Boyd warned that, without increased investment and planning reform, annual flood damages could reach £2.4 billion, with wider economic impacts over a decade totalling about £6.1 billion.
Against that backdrop, Storah has urged the government to strengthen planning rules. Aviva wants a presumption against new developments in high‑risk areas and mandatory property‑level flood resilience measures in building regulations where building in at‑risk zones goes ahead. The insurer argued that effective measures, such as raised electrics, water‑resistant materials and flood doors, can often be installed for under £1,000.
Storah also said tougher rules would be “crucial to ensuring homes are insurable in the future and to protect house values in areas where flooding is predicted”, adding that where and how the UK builds new homes is now a growth and economic‑resilience issue, not just an environmental one.
He also called on ministers to publish updated official figures on how many new homes are being built in medium and high flood‑risk areas and to prioritise preventing further at‑risk development, arguing that increasing housing supply and steering it towards lower‑risk locations “are not mutually exclusive objectives”.
