Glossary
Flood zone
Flood zones classify land by flood risk from rivers and the sea for planning purposes in England. Higher-risk zones trigger sequential tests and flood-risk assessments for many applications.
Even small extensions in Flood Zones 2 or 3 may need a flood risk assessment. Check the Environment Agency maps early.
Scotland (SEPA), Wales (NRW) and Northern Ireland (DfI Rivers) publish their own flood maps and planning tests.
Official source: Flood risk and coastal change (GOV.UK). Checked 27 October 2026.