Electrics: the special location
In England, the space around a bath or shower is a special location under Part P of the Building Regulations. That means:
- Adding a new light, socket or fan point in that space is notifiable work.
- A new circuit, for example for an electric shower or electric underfloor heating, is notifiable wherever it is.
- Replacing the consumer unit is notifiable.
The electrical wiring standard also divides bathrooms into zones that control which fittings can go where. A registered electrician will know these. Use one who belongs to a competent person scheme, so they can self-certify, and ask for the certificate at the end.
Ventilation
Bathrooms need extract ventilation to remove moisture and prevent condensation and mould. Approved Document F sets a minimum intermittent extract rate of 15 litres per second for a bathroom, or an equivalent continuous system. If you are replacing a fan, check that the new one meets the rate and is ducted to the outside.
Drains and waste
Moving a toilet, bath or shower can mean new waste pipes with the right falls, and toilets in particular need a suitable route to the soil stack. New drainage connections fall under Approved Document H. Shower trays at floor level and wet rooms need careful planning so water drains away properly.
Hot water and heating
Work on a gas boiler or gas supply must be done by a Gas Safe registered engineer. Installing an unvented hot water cylinder must be done by a suitably qualified installer and is notifiable. Ask your plumber what your new shower or bath needs from your hot water system before you choose it.
Who to hire
Many bathroom fitters handle plumbing, tiling and carpentry and bring in a registered electrician for the electrics. Agree in writing who is responsible for each certificate. See also wet room or walk-in shower and the order of works for a refit.
Wales, Scotland and Northern Ireland have their own building rules. This guide covers England; elsewhere in the UK, check with your local council.
Last updated: 14 October 2026
