Can I have a socket in my bathroom?

Bathrooms are treated as a special location because wet skin dramatically lowers body resistance, and because a person in a bath is in intimate contact with earthed pipework. The zone system exists to define, by distance from water, what equipment may be installed where — and it is one of the few parts of the wiring regulations a householder genuinely benefits from understanding.

Safety

Step by step

1. Learn Zone 0.The inside of the bath or shower tray itself. Only equipment rated at 12V or lower AC, with the source outside the zones, and rated at least IPX7. In practice, nothing a householder would install.
2. Learn Zone 1.Above the bath or shower tray, up to 2.25m from the floor. Rated at least IPX4. Electric showers, shower pumps and suitably rated lights are permitted here. A 13A socket is not.
3. Learn Zone 2.0.6m outward from the edge of Zone 1, and the same height. Rated at least IPX4. Suitably rated light fittings, extractor fans and shaver supply units are permitted. A 13A socket is not.
4. Understand what is outside the zones.Beyond Zone 2. Here, ordinary accessories are permitted in principle — but a socket is still prohibited unless it is more than 3m horizontally from the boundary of Zone 1. That 3m rule is why almost no domestic bathroom may have a socket.
5. Know what the shaver supply unit is.A shaver supply unit to BS EN 61558-2-5 contains an isolating transformer, so its output is electrically separated from the mains and a fault cannot put mains current through a person to earth. That is why it is permitted where a socket is not. It is limited to a low power output and is not a general-purpose socket.
6. Know how the switching works.Lights and fans in a bathroom are normally switched by a pull cord inside the room, or by a wall switch outside the door. That is because an ordinary switch plate within reach of a wet hand is not acceptable.
7. Know about supplementary bonding.Older installations required supplementary bonding between the pipework, the bath and any exposed metalwork in the bathroom. Modern installations can omit it where all circuits have 30mA RCD protection and the main bonding and earthing are verified. Whether yours may be omitted is a decision for the electrician who tested it.
8. Accept that all of it is notifiable.In England and Wales, any new circuit or addition or alteration in a bathroom is notifiable under Part P. It must be certified by a qualified electrician through a competent person scheme or notified to building control. This applies to adding a fan, moving a light, or fitting a shaver unit.

Tips

• If you want to charge a toothbrush or use a hairdryer, the practical answer used elsewhere in Europe is not available here. Use a socket on the landing.
• Underfloor heating, heated mirrors and towel rails in bathrooms are all notifiable installations. Get them designed and certified rather than added on.
• If you are remodelling, work out socket and lighting positions before the tiling. Zones are measured from finished surfaces and moving anything afterwards is expensive.

Common mistakes

• Running an extension lead into the bathroom — It defeats every reason the zone rules exist. It puts an unrated mains connection in a wet room, often on the floor, and it is one of the clearest avoidable hazards in a house.
• Fitting an ordinary IP20 light fitting in a bathroom because it looks better — Steam condenses inside unrated fittings. That is both a shock risk and the classic cause of an RCD tripping every time someone showers.
• Assuming a room with only a basin is a bathroom — A room containing only a washbasin is not a special location under BS 7671. A cloakroom with a WC and basin follows ordinary rules. The zones apply where there is a bath or a shower.

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