# Part P & notifiable work — who must sign it off > A V2L home-backup arrangement that adds a dedicated inlet circuit, a changeover/transfer switch, or alters the consumer unit is **normally notifiable** under Building Regulations 2010 Reg 12(6A) — so it must be designed, installed, tested and then either certified by an electrician registered with a competent-person scheme (self-certifying), signed off by a building control body, or (in England) certified by a registered third-party certifier. It is not DIY. **Part P is England-specific:** Wales has its own Approved Document P, Scotland uses a building-warrant system with no notifiable/non-notifiable split, and Northern Ireland has no Part P equivalent and no dedicated electrical-safety Technical Booklet (Technical Booklet E is fire safety). Part P decides *who signs it off*; **BS 7671** decides *how it is designed and tested*. **Safety frame.** This is education, not an instruction to carry out work. Work connecting V2L equipment to fixed wiring is safety-critical and may be notifiable under Part P. It must be designed, installed, inspected and tested by a competent person to the current edition of BS 7671. Vehicle manufacturers generally do not sanction back-feeding fixed wiring from V2L outlets; follow manufacturer instructions. ## In short - A V2L inlet circuit, a changeover switch, or any new/replacement consumer unit is **normally notifiable** under Reg 12(6A) of the Building Regulations 2010. - Notifiable means it must be certified by a competent-person-scheme electrician (self-certifying), signed off by building control, or (England) a registered third-party certifier — **not DIY**. - Work in **special locations** (bathroom/shower room) stays notifiable even after the 2013 de-listing of minor jobs. - **Part P is England only.** Wales has its own AD P; Scotland uses a building warrant (no notifiable split); Northern Ireland has no Part P equivalent and no dedicated electrical-safety Technical Booklet. - Part P is the 'who signs it off' layer; **BS 7671** is the 'how it must be designed and tested' layer. Both apply. **Where this stops:** This explains the legal notification and certification duty. It is not a how-to for the wiring — the design, installation, testing and certification are for a competent person. ## The short answer If your V2L home-backup plan adds a dedicated inlet circuit, a changeover or transfer switch, or a new or replacement consumer unit, then in England that work is **notifiable** under the Building Regulations. 'Notifiable' does not mean you ask permission first and then wire it yourself — it means the work must be designed, installed and tested by a competent person and then formally signed off through one of three routes. The car maker does not sanction back-feeding fixed wiring from a V2L outlet, and the contested floating-V2L-on-PME earthing must be designed and **proven by test** by a competent person — Part P is the legal layer that makes that non-negotiable. > **Notifiable is not 'permission to DIY'** — Notifiable work must be carried out and certified by a competent person, or inspected and signed off by building control. Doing notifiable electrical work yourself without that sign-off is a breach of the Building Regulations. ## What 'notifiable' actually means Approved Document P (the government's practical guidance on meeting Part P) splits fixed electrical work in dwellings into work that is *notifiable* and minor work that is not. Notifiable work has to be checked — either by a building control body before and after, or self-certified by a registered competent person who is authorised to confirm it meets the Building Regulations. The 2013 edition narrowed the range of notifiable work and introduced the registered third-party certifier option, but the headline triggers — new circuits and consumer units — were kept. > **Reg 12(6A)** (Building Regulations 2010 (England), confidence: verified) — Installing a new circuit, or a new or replacement consumer unit, in a dwelling is notifiable. A V2L inlet circuit, a changeover/transfer switch, or a consumer-unit alteration normally falls squarely within this — which is exactly the kind of work a V2L backup arrangement involves. _Reference only; standard text not reproduced._ ## Why a V2L changeover is normally notifiable A V2L home-backup scheme is not a plug-in appliance. To switch a small essential board between the grid and the car you add fixed wiring: a dedicated inlet, an interlocked contactor or transfer changeover, and usually an alteration to the consumer unit or a new sub-board. Each of those is the sort of work Reg 12(6A) lists as notifiable. Treat the whole arrangement as notifiable unless a competent person confirms, for the specific job, that it genuinely falls outside the notifiable list. - **A dedicated V2L inlet circuit** — a new circuit, normally notifiable. - **A changeover or transfer switch** feeding an essential board — fixed wiring added to the installation. - **A new or replacement consumer unit / sub-board** — explicitly notifiable under Reg 12(6A). - **Anything passing through a special location** — stays notifiable (see below). > **Special locations stay notifiable** — Additions and alterations to circuits in a bathroom or shower room remain notifiable even though many minor jobs were de-listed in 2013. This matters if a backup feed reaches a property where circuits pass through those locations. ## Who may sign it off (England) In England there are three lawful routes to demonstrate that notifiable work complies. Which one you use is a matter of how the work is organised, not of whether it must be done by a competent person — that part is fixed. 1. **Competent-person self-certification** — an electrician registered with a scheme such as NICEIC or NAPIT carries out the work and self-certifies that it meets the Building Regulations, notifying their scheme. 2. **Building control** — you notify the local authority building control body, which inspects and signs the work off. 3. **Registered third-party certifier** — in England, a registered third-party can certify work done by someone who is not themselves scheme-registered. > **Who may certify** (Approved Document P (England), confidence: verified) — Compliance is shown by a building control body, by a competent-person-scheme electrician self-certifying, or (in England) by a registered third-party certifier. This is the route by which V2L home-backup work is lawfully signed off. _Reference only; standard text not reproduced._ ## Part P is England-specific — the devolved picture This is the trap in any UK-wide guidance. 'Part P' and Approved Document P are the **England** regime. The other three nations regulate domestic electrical safety differently, so the 'is it notifiable / who signs it off' answer changes once you cross a border. The underlying technical standard — BS 7671 — is common across the UK; the *administrative* duty is not. - **England** — Part P / Approved Document P (2013 edition): the notifiable / non-notifiable split described above. - **Wales** — operates its own Part P / Approved Document P regime (devolved in 2011); later England-only amendments mean the live Welsh AD P text can differ. - **Scotland** — the Building (Scotland) Act 2003 and the Building Standards system (standards 4.5 and 4.6, satisfied via BS 7671): a **building-warrant** model with **no** notifiable/non-notifiable Part P split. - **Northern Ireland** — no Part P equivalent and no dedicated electrical-safety Technical Booklet; electrical safety sits under the Building Regulations (NI) framework, with BS 7671 used as the accepted technical standard. Technical Booklet E is fire safety, not electrical safety. > **Don't assume 'Part P' applies UK-wide** — If you are in Scotland there is no Part P notifiable/non-notifiable split — work is controlled through a building warrant. Wales and Northern Ireland have their own instruments. Confirm the regime for the actual nation before relying on any 'Part P' statement. ## Part P vs BS 7671 — two different layers Part P and BS 7671 are often spoken of together, but they do different jobs. **Approved Document P** is the legal/administrative layer: it decides whether work is notifiable and who may certify it. **BS 7671** is the technical layer: it decides how the installation must be designed, earthed, protected and tested. Approved Document P treats BS 7671 as the recognised way to achieve electrical safety, so it points to it rather than restating any wiring detail. A V2L page cites Part P for the notification duty and BS 7671 for the design — the PME/open-PEN earthing, the changeover, the RCD selection. > **§722.411.4.1** (BS 7671, confidence: inference) — The technical heart Part P points to: on a PME (TN-C-S) supply you must not simply rely on the distributor's earth for the EV side without a listed protective measure, because an open PEN can raise metalwork to a dangerous voltage. This is why floating-V2L-on-PME is contested and must be designed and proven by test by a competent person. _Reference only; standard text not reproduced._ > **A version trap worth knowing** — Approved Document P (2013 edition) internally references the much older BS 7671:2008+A1:2011. That is the edition the *guidance document* names — it is not the edition you design to. The live technical standard is BS 7671:2018+A4:2026; keep the two distinct. > **Not confirmed (safety-critical):** What (if anything) BS 7671 Amendment 4:2026 changed for §722 / V2X / V2H / PME / open-PEN is not publicly confirmed in the IET's change-lists. Treat the existing PME/open-PEN framework as carrying forward; do not assert any A4-specific V2X/PME change as fact until confirmed against the published standard. ## What this means for your V2L project Treat a V2L home-backup changeover as notifiable from the start, and plan for a competent person to design, install, test and certify it. That gives you the Electrical Installation Certificate (proving it was tested to BS 7671) **and** the Building Regulations compliance certificate (proving the notifiable-work duty was met). Both matter — for safety, for selling the property later, and for insurance. > **Not confirmed:** Whether your specific V2L changeover also needs DNO notification (separate from the Part P building-control duty) is site-specific. A competent person confirms this for the actual installation. ### How this is made and proven compliant **What governs it:** Building Regulations 2010 (England) Reg 12(6A) — the notifiable-work duty (Approved Document P, 2013 edition); Building Act 1984 — the parent legislation for Part P in England; BS 7671:2018+A4:2026 — the recognised technical standard Approved Document P points to for the installation itself **Who may do it:** A competent person designs, installs and tests the work. In England, compliance is then demonstrated by an electrician registered with a competent-person scheme (e.g. NICEIC, NAPIT) self-certifying, by a building control body, or by a registered third-party certifier. It is not DIY. Wales, Scotland and Northern Ireland use different regimes (see body). **How compliance is demonstrated:** Initial verification to BS 7671 Part 6 with an Electrical Installation Certificate for the new/altered circuits; Notification recorded under Reg 12(6A) — via the competent-person scheme, building control, or a registered third-party certifier (England); A Building Regulations compliance certificate issued to the householder on completion; Special-location work (bathroom/shower room) treated as notifiable regardless of the 2013 de-listing ## FAQ ### Is adding a V2L changeover notifiable? Normally yes, in England. A dedicated inlet circuit, a changeover/transfer switch, or a new or replacement consumer unit is notifiable under **Reg 12(6A)** of the Building Regulations 2010. Treat the arrangement as notifiable unless a competent person confirms otherwise for the specific job. ### Does 'notifiable' mean I can wire it myself if I tell building control? No. Notifiable work must be designed, installed and tested by a competent person and then certified — by a competent-person-scheme electrician self-certifying, by building control, or (in England) by a registered third-party certifier. Notification is not permission to DIY. ### Does Part P apply in Scotland, Wales and Northern Ireland? No — Part P is **England** only. Wales has its own Approved Document P; **Scotland** controls the work through a building warrant with no notifiable/non-notifiable split; Northern Ireland has no Part P equivalent and no dedicated electrical-safety Technical Booklet. The common thread is the technical standard, BS 7671, not the administrative duty. ### What's the difference between Part P and BS 7671? Part P (Approved Document P) is the legal layer — *is the work notifiable, and who signs it off?* **BS 7671** is the technical layer — *how must it be designed, earthed, protected and tested?* Part P points to BS 7671 for the actual installation. Both apply to a V2L changeover. ### Why does Approved Document P mention an old version of BS 7671? The 2013 edition of Approved Document P internally references BS 7671:2008+A1:2011. That is the edition the guidance document names; it is not the edition you design to. The live technical standard is **BS 7671:2018+A4:2026** — keep the two distinct. --- _Author: Martin — qualified UK electrician (BEng Mech Eng; vehicle mechanic)._ _Last reviewed: 15 June 2026. Written against: BS 7671:2018 + A4:2026._ _Status: reviewed. General information, not project-specific design advice._ _[How we source this](/methodology) — evidence hierarchy, confidence flags and source policy._ ## Sources 1. Approved Document P — Electrical safety (Building Regulations, England), 2013 edition (GOV.UK) — https://www.gov.uk/government/publications/electrical-safety-approved-document-p (Crown copyright, Open Government Licence; cited and paraphrased by reference) 2. Planning Portal — Part P: Electrical safety (Approved Document P) — https://www.planningportal.co.uk/applications/building-control-applications/building-control/approved-documents/part-p-electrical-safety/approved-document-p/ 3. IET — Part P, Scotland & Northern Ireland (devolved building regulations) — https://electrical.theiet.org/bs-7671/building-regulations/part-p-scotland-and-northern-ireland/ 4. BS 7671:2018+A4:2026 — Requirements for Electrical Installations (IET/BSI) — https://electrical.theiet.org/bs-7671-18th-edition-wiring-regulations/about-bs-7671/ (the technical standard Part P points to; cited by clause only, text not reproduced)