Planning

Building in Flood Zones

What you need to know about building new properties in flood risk areas — regulations, design, and resilience.

Last updated: 2026-03-27

Building in Flood Zones

Can You Build in a Flood Zone?

Yes, but with significant constraints. The NPPF's Sequential Test steers development away from flood zones, but where building is justified, flood-resilient design is essential.

Design Principles

  • Raised floor levels: At least 300mm above the design flood level plus climate change allowance
  • Flood-resilient materials: Waterproof materials below the design flood level
  • Safe access and egress: Ensure occupants can enter and leave safely during a flood
  • Flood compensation: If the building displaces floodplain storage, provide equivalent storage elsewhere
  • SuDS: Manage surface water so it does not increase flood risk elsewhere

Building Regulations

Part H covers drainage and waste disposal, including protection from surface water flooding.

Innovative Flood-Resilient Design

  • Wet-proofed ground floors: Designed to flood and drain without damage
  • Amphibious buildings: Structures that rise with floodwater
  • Floating homes: Permanently on water
  • Raised living spaces: Habitable rooms above ground floor

Frequently Asked Questions