Building Regulations and Solar Part P: What UK Homeowners Actually Need (2026)

Solar panel installation in the UK must comply with Part P of the Building Regulations, which covers electrical safety in dwellings. This means the electrical work involved – connecting panels to inverters and connecting inverters to your consumer unit – is “notifiable work” that must either be done by a registered competent person or be approved by your local authority building control.

In practice, using an MCS-certified installer handles all Part P compliance automatically. MCS installers are registered with competent person schemes that allow them to self-certify their electrical work, issue the required certificates, and notify building control on your behalf. You receive the documentation needed for SEG registration, insurance, and future property sale.

This guide explains Part P requirements, how they apply to solar installations, what certificates you should receive, other relevant building regulations, and the different rules in Scotland, Wales, and Northern Ireland.

Quick Overview

What Is Part P?

Part P Basics

The full text of the regulation – what counts as notifiable work, the three certification routes, the technical requirements – is published on GOV.UK as Approved Document P: Electrical Safety. It’s the authoritative source for England (and is also applied to “excepted energy buildings” in Wales).

Why It Applies to Solar

What “Notifiable” Means

Competent Person Schemes

What Are They?

Electrical Competent Person Schemes

How It Works for Solar

MCS and Part P

MCS Certification Includes Part P

Why MCS Handles Everything

Documentation From MCS Installer

For more on what MCS actually means and why almost every UK installer is signed up to it, see our quote-checking guide which covers verifying installer credentials before signing.

Electrical Installation Certificate

What It Contains

Why It Matters

Keeping Your Certificate

BS 7671 Wiring Regulations

What Is BS 7671?

Solar-Specific Requirements

Key Safety Requirements

Some of these protective devices have specific evolving requirements – for example, DC arc-fault detection is increasingly being added to new installations. See our guide to arc-fault detection in solar systems.

Other Building Regulations

Part A: Structure

Part L: Energy Conservation

Part B: Fire Safety

Planning vs Building Regulations

Key Differences

When Planning Applies

DIY Installation

Is DIY Legal?

DIY Building Control Route

The Planning Portal’s summary of Approved Document P is a useful plain-English overview if you’re considering this route, including the third-party certifier alternative introduced in the 2013 edition.

Why DIY Is Problematic

Non-Compliance Consequences

Risks of Non-Compliant Installation

Regularisation

When Selling Property

From the buyer’s perspective, certificate gaps are the single most common conveyancing snag with solar-equipped homes. See our guides to buying a house with solar panels and buying a house with leased solar panels for more on what to check.

Scotland

Scottish Building Standards

Key Differences

Wales

Welsh Building Regulations

Key Points

Northern Ireland

NI Building Regulations

Key Differences

Listed Buildings and Conservation Areas

Additional Requirements

Building Regulations Still Apply

If you live near or share a boundary with an objector, see our guide to whether neighbours can object to your solar panels.

New Build Properties

Solar on New Builds

Buying New Build With Solar

Checklist: What You Should Receive

Essential Documents

Additional Useful Documents

Frequently Asked Questions

Compliance Questions

Practical Questions

If you’re adding a battery later, the rules are essentially the same as for the original install – see our guide to adding a battery to existing solar panels.

Summary

Part P of the Building Regulations applies to solar panel installations because they involve electrical work in dwellings. The regulations require that this work either be done by a member of a competent person scheme (who can self-certify) or be approved by local authority building control through formal application and inspection.

In practice, using an MCS-certified installer makes Part P compliance automatic. MCS installers must be members of competent person schemes and qualified to BS 7671 standards. They install, test, and certify the work, then notify building control through their scheme. You receive an Electrical Installation Certificate as proof of compliance, along with your MCS certificate for SEG registration.

The key action for homeowners is simple: use an MCS-certified installer and ensure you receive all documentation after installation. Keep your Electrical Installation Certificate safe – you’ll need it for SEG registration, may need it for insurance, and will definitely need it when selling your property.

DIY installation is technically possible but creates significant complications: no MCS certificate means no SEG payments, you must arrange your own building control application and inspection, and future property sales may be complicated by questions about compliance. For almost all homeowners, professional MCS installation is the only practical route.