ProjectCalcThe requirement
Part P applies to electrical installations in dwellings. Approved Document P (2013 edition) states at paragraph 1.1 that electrical installations should be designed and installed in accordance with BS 7671:2008 incorporating Amendment No 1:2011 (the IET Wiring Regulations), and that the information provided for the installation should comprise the items listed in BS 7671 — including electrical installation certificates or reports describing the installation, and details of the equipment, such as consumer units and residual current devices (RCDs).
The document also notes that since 2013 the requirement for the work to be notified has been reduced to a defined list, and that registered competent persons can self-certify notifiable electrical installation work as an alternative to using a building control body.
What is notifiable
Paragraph 2.5 reproduces the list from regulation 12(6A). A person intending to carry out building work to which Part P applies is required to give a building notice or deposit full plans where the work consists of:
- (a) the installation of a new circuit;
- (b) the replacement of a consumer unit; or
- (c) any addition or alteration to existing circuits in a special location.
What a "special location" is
Regulation 12(6A)(9) defines it. Within a room containing a bath or shower, it is the space surrounding a bath tap or shower head which extends:
- vertically from the finished floor level to a height of 2.25 metres, or to the position of the shower head where it is attached to a wall or ceiling higher than 2.25 m above that level; and
- horizontally, where there is a bath tub or shower tray, from the edge of the bath tub or shower tray to a distance of 0.6 metres; or, where there is no bath tub or shower tray, from the centre point of the shower head to a distance of 1.2 metres.
A room containing a swimming pool or a sauna heater is also a special location.
Diagram 2 in the document shows that space, and carries a note worth reading twice: "Socket-outlets should not be located within 3 m of a bath tub or shower tray."
What is not notifiable
Paragraph 2.7: all other electrical installation work is not notifiable — namely additions and alterations to existing installations outside special locations, and replacements, repairs and maintenance anywhere. The worked examples in the document make the boundary clear: installing a built-in cooker is not notifiable unless a new cooker circuit is needed; connecting an electric gate or garage door to an existing isolator switch is not notifiable, but installing a new circuit from the consumer unit to the isolator is.
Consumer units and Part M
Paragraph 1.4 concerns making controls easy to reach: wall-mounted socket-outlets, switches and consumer units in new dwellings should be easy to reach and operate. It notes that Approved Document M does not recommend a height for new consumer units, but that one way of complying with Part M in new dwellings is to mount consumer units so that the switches are between 1350 mm and 1450 mm above floor level.
What this changes about the job
- A bathroom re-fit is usually notifiable if any existing circuit is altered inside the special location — and the zone is a 2.25 m high, 0.6 m deep envelope around the bath or shower.
- Replacing a consumer unit is notifiable, regardless of where it is.
- Sockets and bathrooms. The 3 m note is about socket positions relative to a bath or shower tray, and it is the figure that most often kills a layout after the tiling is up.
- Use a registered competent person, or notify building control before the work starts — this is one of the few areas where the order of operations matters administratively as well as physically.
The editions this document cites
These are British and European standards this approved document names. The edition column is the one the document itself cites; the last column is what BSI catalogues today (22 September 2026). Where the two differ, the document is citing an edition that has since been replaced or withdrawn — that is normal for an approved document, and it is why the current edition is listed beside it rather than instead of it.
| Standard | Title as published | Edition cited by the approved document | Current edition (BSI) |
|---|---|---|---|
| BS 7671 | Requirements for Electrical Installations. IET Wiring Regulations | BS 7671:2008 incorporating Amendment No 1:2011 — cited by Approved Document P | BS 7671:2018+A4:2026 — Current (15 April 2026) |
Source: BSI catalogue records read at knowledge.bsigroup.com on 22 September 2026. Each title, designation, status and date in the last two columns was read from the BSI catalogue page for that standard.
Last verified 22 September 2026. Every requirement quoted on this page was read from the primary source listed below on that date, not from a summary. If a figure could not be confirmed in the primary source it is not on this page.
Where these figures come from
- Approved Document P: Electrical safety, 2013 edition (paragraphs 1.1, 1.4, 2.5-2.7 and Diagram 2; regulation 12(6A)) — GOV.UK publications, "Electrical safety: Approved Document P", checked 22 September 2026.
- BSI catalogue (“BSI Knowledge”) — product record for each standard listed above: title, current edition and status — knowledge.bsigroup.com, checked 22 September 2026.
Guidance only, not advice
This page is a plain-English summary of published regulations and standards, written to help you plan a job. It is not professional advice, it is not a substitute for the actual document, and it is not a building-control decision.
Building regulations are enforced by your local authority (or an approved inspector) and the facts of a particular job can change the answer. Confirm with your local building control before you start work, and where a job is structural, get it designed by a suitably qualified person. If this page and the source document disagree, the source document wins.