Trades master copy
Last reviewed: March 2026
What Part P is
Part P is the bit of Building Regulations that covers fixed electrical installations in and fed from dwellings - including gardens and outbuildings on the same meter.
It says that electrical work must be designed and installed so people are protected from fire and electric shock. That's the legal test you're working to.
This guide is a summary to make Part P easier to use on site. It does NOT replace Approved Document P or BS 7671. You must read and follow the full Approved Document P and the current BS 7671 (18th Edition with latest amendments) for detailed requirements.
This guide is written for England. Wales, Scotland and Northern Ireland have their own versions of building regulations - the principles are similar but the documents and approval routes differ, so check local requirements if you're working outside England.
Where it applies on your jobs
Part P applies to electrical work on the consumer's side of the meter:
- Houses, flats and maisonettes, including fixed equipment on outside walls.
- Sheds, detached garages, greenhouses and other outbuildings fed from the dwelling.
- Garden electrics - lights, pond pumps, etc.
- Common areas of blocks of flats.
- Small commercial spaces on the same meter as a dwelling (e.g. a shop under a flat).
It does NOT apply to separately metered commercial premises, or lift power in blocks of flats (other regulations still apply).
Notifiable vs non-notifiable work
In England, only these are "notifiable" under Part P:
- Installing a new circuit from the consumer unit.
- Replacing a consumer unit.
- Any addition or alteration to an existing circuit in a special location (bath/shower zones, swimming pools, saunas).
Everything else is non-notifiable, but still must:
- Comply with BS 7671.
- Be inspected, tested and certificated properly.
Quick reference table - typical jobs
| Job on site | Notifiable? | Notes |
|---|---|---|
| Move or add sockets on existing ring in kitchen | No | Non-notifiable, but needs test + Minor Works cert. |
| New radial circuit to garden office | Yes | New circuit from CU. |
| Swap like-for-like light fitting in lounge | No | Repair/replacement anywhere is non-notifiable. |
| Fit new consumer unit | Yes | Always notifiable. |
| Add fan or shaver socket in bathroom zone | Yes | Addition/alteration in special location. |
| Replace damaged bathroom fitting on existing circuit | No | Replacement only, even in special location. |
| New dedicated boiler supply from the consumer unit | Yes | New circuit from CU, even if it only feeds the boiler. |
| Connect new boiler to existing fused spur / circuit | No | Using existing circuit. Still needs correct isolation, RCD protection and cert. |
| Install EV charger on its own new circuit | Yes | New circuit; plus you've got to meet EV charger standards and DNO/earthing requirements. |
| Install outside socket for a portable hot tub, fed from existing circuit via fused spur | No | Non-notifiable unless it creates a special location. Check RCD protection and manufacturer's requirements. |
| Run new circuit to fixed outdoor spa or permanent hot tub | Yes | New circuit; higher risk environment, so treat it like a bathroom/pool job in terms of care and paperwork. |
Routes to compliance for trades
For notifiable work you must use one of these routes:
Registered Competent Person - you (or your spark) are in a Part P scheme and self-certify, notify, and issue Building Regulations compliance certificates.
Registered third-party certifier - a registered certifier inspects/tests your work and issues the paperwork. Must be appointed before you start.
Building Control route - you notify the council/approved inspector before work starts, they arrange whatever inspection/testing they think is needed and issue a completion certificate.
If you aren't registered and don't bring in a certifier or Building Control, notifiable work will not be compliant, no matter how neat it looks.
Who is responsible for what
On a typical job:
- The electrician is responsible for design, installation, inspection, testing and issuing BS 7671 certificates.
- Other trades (builder, kitchen fitter, bathroom installer) are responsible for not damaging or altering electrics in a way that breaks BS 7671 or makes the installation unsafe.
- The client/owner is the one Building Control will chase if the work doesn't comply. Enforcement notices land with them, then they come back to you.
If you're the main builder running the job and you bring in an electrician who isn't registered and doesn't sort the Part P side properly, that's your problem too - not just theirs. You're the one the client sees as "in charge".
Simple rule to drum into your team
If it's a new circuit, a board change, or any addition/alteration in bathroom/pool/sauna zones, stop and involve a Part P-registered electrician or Building Control before you touch it.
On-site checklist
You can re-use this pattern for every section of the regs - just swap in the right triggers.
Before you start
- Check: Is this job in or fed from a dwelling, garden or outbuilding on the same meter?
- Decide: Is it a new circuit, consumer unit change, or work in bathroom/pool/sauna zones?
- If YES to any of those, agree in writing who is notifying - your own scheme, third-party certifier, or Building Control.
- Confirm the spark's status: registered competent person or not, and get scheme/registration number if they are.
While you're working
- Do not bury, cut, notch or drill where it will compromise cables or containment.
- Do not alter circuits beyond your competence or outside the agreed design.
- Keep routes, depths and locations consistent so the installation can be tested and documented.
When you finish
- Make sure the electrician has inspected, tested and issued the right BS 7671 certificate (EIC or Minor Works).
- For notifiable work, make sure the Building Regulations compliance certificate or Building Control completion certificate is issued and filed with the job paperwork.
- Record what you altered (drawings, photos, notes) so there is a clear trail if the job is queried later.
Sources
Based on:
- Approved Document P: Electrical safety - dwellings (current edition on gov.uk).
- BS 7671 (IET Wiring Regulations, 18th Edition with latest amendments).
- Local authority and industry guidance on notifiable vs non-notifiable work and Part P compliance.
This guide was last reviewed March 2026. SiteKiln does not provide legal, financial or tax advice. All content is for general information purposes only. Always seek professional advice for your specific situation.
Common questions
Is Part P electrical self-certifiable?
Only if you're registered with a Competent Person Scheme such as NICEIC, NAPIT, ELECSA or Stroma. Registered electricians can self-certify notifiable work and issue the Building Regulations compliance certificate. Anyone else must notify Building Control, pay them to inspect, and have them certify it.
Part P Electrical Safety guide.
Know someone who needs this?
Working in Wales? The building rules are different. See our Working in Wales guides.
Working in Scotland? Building standards work differently. See our Working in Scotland guides.
Working in Northern Ireland? The system uses Technical Booklets. See our Working in Northern Ireland guides.
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