Part P Building Regulations Explained: What UK Homeowners Can and Can't DIY

Before you touch a wire in a UK home, Part P asks a simple question: does this work need to be inspected, or can you do it yourself? Get the answer wrong and the consequences range from a failed house sale to a voided insurance policy. Get it right and the work is legally compliant, safe, and properly documented.

Part P is the section of the UK Building Regulations that covers fixed electrical installations in domestic properties. It has been in force since 2005 (England & Wales) and applies to every electrical job that goes beyond simple like-for-like maintenance. This guide explains exactly what it covers, what is and is not notifiable, and the three routes to making sure your work is compliant.

💡 Plan first, then build. Use ElectraSim to design and test your circuit on screen before any cable is run. You can validate the topology, check protection, and brief a qualified electrician with a clear diagram. Open ElectraSim →

What Is Part P?

Part P is one of 14 parts of Schedule 1 to the Building Regulations 2010 (England) and the equivalent regulations in Wales (2014 amendments). It is enforced by local authority Building Control, not by the electrical industry.

Its purpose is straightforward: fixed electrical installations in dwellings must be safe. To achieve that, Part P requires that:

1. Reasonable provision is made in the design and installation of electrical installations to protect persons operating, maintaining or altering the installation from fire or injury.
2. Sufficient information is provided so that persons wishing to operate, maintain or alter an electrical installation can do so safely.

In practical terms, Part P:

• Defines what counts as a “fixed electrical installation” in a dwelling
• Separates that work into notifiable and non-notifiable categories
• Requires notifiable work to be either carried out (or certified) by a registered competent person OR notified to Building Control for inspection
• Makes the homeowner ultimately responsible for compliance

Important: Part P does not replace BS 7671 (the IET Wiring Regulations, 18th Edition). BS 7671 is the technical standard — how the work is done. Part P is the legal framework — whether the work must be inspected and by whom. The two are complementary. A Part P-compliant installation must also be BS 7671-compliant; being BS 7671-compliant does not, on its own, satisfy Part P.

What Is a Dwelling Under Part P?

Part P applies to “a building or part of a building used, or intended to be used, as a dwelling.” This includes:

• Houses, bungalows, flats, maisonettes
• Sheltered accommodation, care homes (residential rooms)
• Houses in multiple occupation (HMOs)
• Garden buildings where the supply originates from the dwelling’s consumer unit

Part P also applies to parts of non-dwellings supplying dwellings — for example, a commercial landlord’s distribution system feeding residential flats above a shop. Common areas of flats (stairways, hallways, shared supplies) are covered.

Not covered by Part P:

• Commercial or industrial premises (covered by the Electricity at Work Regulations 1989)
• Agricultural installations
• Caravans, motor homes, boats
• Garden sheds, summerhouses, and outbuildings supplied from a separate meter or sub-supply not originating from the dwelling
• Solar PV, battery storage, and other microgeneration — covered by other regulations and standards (BS 7671 Section 712, the MCS standards, G98/G99)

If your outbuilding is supplied by a new circuit from the house consumer unit, it is covered. If it has its own separate meter and supply from the DNO, it is not a “fixed electrical installation in a dwelling” and Part P does not apply.

Notifiable vs Non-Notifiable Work

This is the part most homeowners get wrong. Part P divides electrical work into two categories: work that must be inspected or certified (notifiable), and work that does not need to be notified (non-notifiable — sometimes called “minor work”).

What Is Notifiable Work

Notifiable work is any fixed electrical installation work that adds a new circuit, alters an existing circuit in a “special location” (kitchen, bathroom, outdoors, etc.), or significantly extends an existing circuit. The full list of notifiable work is:

What Is Non-Notifiable Work (Minor Work)

Part P also lists work that does not need to be notified. This is sometimes called “minor work” or the “minor works exemption”. The full list:

The crucial caveat for “minor works”:

The work must be carried out to BS 7671 in every case. Non-notifiable does not mean “any standard is acceptable.” If you add a spur to a ring and wire it wrong, causing a fire, you are still liable — both criminally (under the Building Regulations as a whole, and possibly the Health and Safety at Work etc. Act 1974 if anyone is injured) and civilly (insurance, sale of property).

Minor work also requires that the existing circuit is capable of supporting the addition (correct rating, RCD protected, in good condition). Adding a 16 A socket to a 6 A lighting circuit is non-notifiable but unsafe — and you are still on the hook.

📖 Related: What is an EICR and When Do You Need One? — an EICR is how you confirm the existing circuit is in a fit state for any addition.

The Three Routes to Compliance

When the work is notifiable, you have three legal routes. Exactly one of these must apply for the work to be Part P-compliant.

Route 1: Use a Registered Competent Person (Most Common)

A registered competent person is an electrician or electrical installer who is registered with a government-approved scheme such as:

• NICEIC (National Inspection Council for Electrical Installation Contracting)
• NAPIT (National Association of Professional Inspectors and Testers)
• ELECSA
• STROMA (now folded into NAPIT)
• SELECT (Scotland)
• NICEIC Domestic Installer scheme (now the most common for small domestic work)

These schemes are authorised by the Department for Levelling Up, Housing and Communities (DLUHC) — formerly DCLG — to operate under the Building Regulations as Competent Person Schemes (CPS).

When you use a registered competent person, the route is:

1. You agree the scope of work and a quote
2. The electrician does the work to BS 7671
3. The electrician self-certifies the work and issues an Electrical Installation Certificate (EIC)
4. The scheme operator notifies Building Control on the electrician’s behalf within 30 days
5. You receive a Building Regulations Compliance Certificate (often the same document as the EIC) — this is the proof you need for insurance and house sales

The homeowner does almost nothing. The electrician handles notification, certification, and compliance.

Cost implication: A registered electrician’s quote is typically higher than an unregistered sparky because of scheme fees, insurance, calibration of test instruments, and the cost of being able to self-certify. For a small job (one new socket), this can feel disproportionate. For a full rewire, it is the standard route and expected.

Always ask to see the scheme registration card before work starts. Any registered electrician can show you their card or a printed registration certificate. Their registration number must appear on the EIC.

Route 2: Notify Building Control Directly (For Non-Registered Installers)

If you (or your chosen installer) are not registered, the work must be notified to local authority Building Control before it starts. The route is:

1. Submit a Building Notice (or Full Plans application) to your local authority — typically online, sometimes a fee of £150–£500 depending on the authority
2. Pay the prescribed fee
3. Carry out the work to BS 7671
4. Building Control inspects the work — usually one or two visits during the work, plus a final inspection
5. On satisfactory completion, Building Control issues an Electrical Completion Certificate (ECC) via the registered electrician who carried out the testing, OR the work is tested and signed off by a suitably qualified third-party inspector

This route is uncommon for homeowners because:

• It is more expensive (the Building Control fee is on top of the electrician’s labour)
• It is slower (inspection appointments, paperwork)
• It puts the homeowner in the role of project manager

It is the correct route if you are doing the work yourself (under your own competence) and the work is notifiable. In practice, most homeowners using this route are doing significant work — a rewire, a new consumer unit, a major extension — where the Building Control fee is small in proportion to the work.

Route 3: Non-Notifiable Work (No Notification Required)

For the work categories listed in the non-notifiable table above, no notification, certificate, or Building Control involvement is required. The work is still required to comply with BS 7671, but no third party inspects or certifies it.

This is the route for almost all small DIY work — replacing a damaged socket, adding a switch, swapping a light fitting.

However: for your own protection, it is still best practice to obtain a Minor Works Certificate (BS 7671 Form 3) from a qualified electrician for any work that materially alters a circuit, even if Part P does not require it. A Minor Works Certificate:

• Documents the work for future reference
• Identifies any defects in the existing circuit uncovered during the work
• Provides evidence of competence and care in the event of an insurance claim
• Is often requested by buyers’ solicitors during a house sale

What Happens If You Skip Notification

This is the question that has real consequences. The honest answer is that enforcement is rare, but the consequences when it bites are severe.

During the Work or Immediately After

• A neighbour or council inspection reports the work. Building Control may issue a Section 36 notice requiring you to open up the work for inspection
• An incident (fire, shock) occurs. The Fire and Rescue Service, a coroner, or an insurance assessor finds unnotified work. This can lead to prosecution under the Building Regulations and the Health and Safety at Work etc. Act 1974

When You Sell the House

This is where most unnotified work is caught. The buyer’s solicitor will:

• Request the Electrical Installation Condition Report (EICR)
• Request copies of all Electrical Installation Certificates (EICs) and Minor Works Certificates for the past 20+ years
• Compare those documents against the work visible in the property

If work is visible (new consumer unit, new circuits, recent additions) with no certificate:

• The solicitor flags it as a pre-contract enquiry query
• You must either retrospectively notify the work (which is more expensive than notifying in advance), or obtain a retrospective Electrical Installation Condition Report from a registered electrician confirming the work is safe to BS 7671
• In the worst case, the buyer reduces the offer, demands remedial work, or walks away

The retrospective route: Building Control can serve a Regularisation Certificate (formerly a “regularisation application”) for work that was done without notification. The fee is typically 50–100% higher than the original fee would have been, plus the cost of opening up the work for inspection. For most homeowners, this is far more painful and expensive than notifying in advance.

Insurance

Most home buildings-and-contents insurance policies require that electrical installations are maintained in a safe condition and that statutory requirements are met. If a fire is traced to unnotified electrical work, insurers can:

• Refuse to pay the claim (citing breach of policy condition)
• Pay the claim but pursue recovery from the homeowner
• Cancel the policy and flag you as a higher-risk customer

📖 Related: 5 Common Electrical Wiring Mistakes (and How to Avoid Them) — unnotified work is a legal issue, but the unsafe work that often accompanies unnotified DIY is the real problem.

The Criminal Side

A failure to comply with Building Regulations is a summary offence under the Building Act 1984. Prosecution is rare, but possible. In practice, prosecution is reserved for:

• Repeated non-compliance
• Work that has caused injury or damage
• Work done by a person posing as a qualified professional (fraud)

The Cost of Notification

Homeowners often delay notifying because of perceived cost. The actual numbers are modest:

For a typical £200–£500 domestic electrical job, the registered electrician route is by far the cheapest when all costs are counted: the electrician’s quote includes the notification, the certificate, and the compliance paperwork. The “saving” of using an unregistered person is usually a few percent, against the loss of paperwork protection worth thousands when the house is sold.

Common Part P Scenarios

The Three Things a Homeowner Must Do

1. Before the work starts: Determine whether the work is notifiable. When in doubt, ask a registered electrician or call your local Building Control office. A 10-minute phone call avoids a £500 retrospective bill.
2. For notifiable work: Either instruct a registered competent person who will self-certify and notify, or submit a Building Notice to your local authority and have the work inspected.
3. Keep the paperwork: EICs, Minor Works Certificates, Building Control compliance certificates, and EICRs. Store them with the house deeds. Your buyer — or your insurer, or a future you — will thank you.

Planning a Part P-Notifiable Job in ElectraSim

Part P does not stop you from planning a job yourself. The restriction is on the installation and certification. Using ElectraSim before you call an electrician is a smart move:

1. Design the circuit — place the consumer unit, run the cable routes, position accessories. Verify the topology is sound
2. Validate the protection — confirm the MCB/RCBO ratings match the cable, the RCD coverage is correct, and the earthing arrangement is appropriate for the location
3. Brief the electrician — instead of describing what you want in words, show them a working diagram. They can quote accurately, flag issues early, and quote a fixed price rather than an estimate
4. Test ideas safely — ElectraSim’s fault simulation mode lets you inject reverse polarity, open circuits, and missing earths to see exactly what each fault does — invaluable for understanding why Part P requires the work to be certified

🔍 The simulator runs a full graph traversal on every change — the same logical analysis an electrician applies during testing. Try it free →

Frequently Asked Questions

Can I do my own electrical work in the UK?

Yes — but with restrictions. Non-notifiable work (like-for-like replacements, minor additions in non-special locations) can be done by a competent homeowner. Notifiable work must be carried out or certified by a registered competent person, or notified to Building Control for inspection.

Do I need an electrician to change a socket?

For a like-for-like replacement in a non-special location, no. For adding a new socket, replacing a damaged one in a kitchen or bathroom, or any change to the circuit, the rules above apply.

What happens if I sell a house with unnotified electrical work?

The buyer’s solicitor will likely flag the absence of an EIC. You have three options: retrospectively notify (expensive), obtain a retrospective EICR from a registered electrician, or accept a reduced offer / abortive sale.

Is Part P the same in Scotland and Northern Ireland?

No. Scotland has its own Building Standards system (the “Building (Scotland) Regulations 2004”) with similar requirements. Northern Ireland has its own Building Regulations. The principles are similar but the procedural details differ — check with your local authority.

How long does Building Control notification take?

For a Building Notice, notification is typically 48 hours before work starts. The first inspection usually takes 5–10 working days to arrange. A full rewire might need 2–3 inspections (first-fix, second-fix, final).

Is there a Part P register I can check?

Yes. The Electrical Competent Person Register at electricalcompetentperson.co.uk lists every registered electrician in England and Wales. Always check an electrician’s registration before they start work.

Does Part P require an EICR?

Not directly. An EICR is required in different circumstances: every 10 years for owner-occupied homes, every 5 years for rented properties (under the Electrical Safety Standards in the Private Rented Sector (England) Regulations 2020), and at change of occupancy for HMOs. But an EICR is the easiest way to demonstrate that existing wiring is in a sound state, which is a prerequisite for adding new non-notifiable work to a circuit.

Can I install an EV charger myself under Part P?

Technically yes, via the Building Control notification route, but in practice almost everyone uses an OZEV-authorised installer because:

• The charger must be OZEV-eligible (Government grant schemes require it)
• The installer must be OZEV-authorised to claim any grants
• The DNO must be notified in most cases (separate from Part P)
• The PEN-fault protection and earthing requirements are technically demanding

Quick Reference: Part P in 30 Seconds

• Part P = UK Building Regulations for fixed electrical installations in dwellings
• Notifiable work = new circuits, consumer unit changes, work in special locations (kitchen, bathroom, outdoors)
• Non-notifiable work = like-for-like replacements and minor additions in non-special locations
• Three compliance routes = (1) registered competent person, (2) notify Building Control, (3) non-notifiable exemption
• Homeowner responsibility = know which category the work is in, keep all certificates with the deeds
• Consequences of skipping = retrospective notification costs, insurance issues, sale problems, criminal liability in the worst case

Want to Plan Before You Book?

Use ElectraSim to design and test your circuit before you call a registered electrician. You will arrive at the conversation with a clear diagram, a validated topology, and a list of specific questions — saving you an hour of the electrician’s time and keeping their quote focused. Open ElectraSim →