UK Bathroom Electrical Zones (BS 7671 – IET Wiring Regulations)

When installing electric or dual-fuel towel radiators, compliance with BS 7671 and Building Regulations Part P is mandatory. Bathroom areas are divided into electrical zones based on proximity to water sources. The location of the towel radiator, power supply, and controls must respect these zones.

Overview of Bathroom Zones

• Zone 0 – Inside the bath or shower

• Zone 1 – Above the bath or shower up to 2.25 m

• Zone 2 – 0.6 m horizontally beyond Zone 1

• Outside Zones – All remaining areas

          Ceiling
  ─────────────────────
        ZONE 1
  │──────────────────│   ← up to 2.25 m high
  │                  │
  │     Bath Area     │
  │     ZONE 0        │
  │                  │
  └──────────────────┘
  ←── 0.6 m ──→
     ZONE 2

Outside Zone (Safe Area)

Key Notes for Installers

• Zone 0:

  • No towel radiators permitted

  • Only SELV (max 12V AC / 30V DC) equipment allowed

• Zone 1:

  • Electric towel radiators allowed only if manufacturer-approved

  • Minimum IPX4 rating

  • No switches or fused spurs permitted

• Zone 2:

  • Electric towel radiators allowed

  • Minimum IPX4 (IPX5 recommended)

  • No socket outlets

  • Controls generally discouraged unless specifically rated

          Ceiling
  ─────────────────────
        ZONE 1
   (Radius 1.2 m)
        │
        │
      Shower
        │
        │
   ZONE 0 (Floor)

Installer Guidance

• Zone 1 extends 1.2 m horizontally from the fixed shower head

• Height remains 2.25 m from finished floor level

• If a shower tray is present, Zone 0 is limited to the tray area

Zone	Electric Towel Radiator	Notes
Zone 0	❌ Not permitted	No heating appliances
Zone 1	⚠️ Restricted	IPX4+, no controls
Zone 2	✔️ Permitted	IPX4+, no sockets
Outside Zones	✔️ Recommended	Best location

 

Isolation, Switching & Controls (Critical Compliance Points)

• All electric towel radiators must have:

  • Local double-pole isolation

  • Isolation located outside Zones 0, 1 & 2

• Common solutions:

  • Fused spur outside the bathroom

  • Switched FCU above door height outside zones

• Timers and thermostats should:

  • Be outside zones where possible

  • Not be influenced by localised heat from the radiator

Installer Checklist (Electrical Zones)

✔ Confirm bath/shower layout before first fix
✔ Identify Zone 1 and Zone 2 extents correctly
✔ Verify IP rating on product data sheet
✔ Position fused spur outside restricted zones
✔ Ensure Part P compliance and certification

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Trade Summary

For UK installations, outside Zone 2 is always the safest and simplest location for electric and dual-fuel towel radiators. Correct zone identification reduces risk, avoids non-compliance, and prevents costly remedial work. When in doubt, treat the towel radiator as a fixed electrical appliance and default to the safest permitted area.