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Bathrooms are divided into zones by proximity to water. Zone 0 is inside the bath or shower basin; Zone 1 is above it to 2.25m; Zone 2 extends 0.6m beyond Zone 1 and around a washbasin. Each zone sets a minimum IP rating and restricts what may be installed.
6 questions in this topic. General UK guidance, not advice about a specific property.
Bathrooms are divided into zones by proximity to water. Zone 0 is inside the bath or shower basin; Zone 1 is above it to 2.25m; Zone 2 extends 0.6m beyond Zone 1 and around a washbasin.
Each zone sets a minimum IP rating and restricts what may be installed. Sockets (other than shaver supply units) are not permitted within 3m of Zone 1, and all circuits serving the room need RCD protection.
Standard 13A sockets are not permitted within 3m of the boundary of Zone 1. In most domestic bathrooms that rules them out entirely. A shaver supply unit to BS EN 61558-2-5 is permitted outside Zones 0 and 1 and is the normal solution.
Large bathrooms occasionally have space beyond the 3m limit, but that has to be measured, not assumed.
Mechanical extraction is required in bathrooms and shower rooms under Part F where there is no adequate alternative, and it is the practical answer to condensation and mould. Common options are a timer overrun (runs on after the light) or a humidity-sensing unit.
The fan must suit its zone, be RCD protected, and have an isolator so it can be switched off for maintenance. A timer model needs a permanent live as well as the switched one.
Supplementary bonding in a bathroom may be omitted where three conditions are all met: all circuits serving the room have 30mA RCD protection, all circuits satisfy the disconnection times, and effective main protective bonding is in place.
In older installations one of those is often missing, which is why supplementary bonding is still frequently required — or an upgrade elsewhere is needed to allow it to be omitted.
Electric underfloor mats or cables are laid before the floor finish, fed from a suitable circuit with RCD protection, and controlled by a thermostat with a floor sensor. The thermostat position has to be chosen with the room zones in mind.
Insulation boards under the mat make a substantial difference to how it performs. The mat is tested before, during and after the floor is laid — once it is tiled over, a damaged element is a serious problem.
Yes, provided the fitting's IP rating suits its zone and it is fed correctly — usually from a fused connection unit with the switch outside the zones, or via a flex outlet for a permanently connected item.
Check the manufacturer's stated zone suitability before buying; some attractive mirrors are only rated for positions further from the bath than people expect.