Part S Building Regulations:
The Complete Guide for Developers

What is a cable route?

A safe, unobstructed route from a metered supply point to the future charge point position. It includes space at the supply point, the containment, a labelled future connection location, and enough room to install a charge point safely. It doesn't include the cable itself, busbars, plinths, barriers or any electrical upgrades. That's the main reason a compliant duct doesn't always mean an affordable charge point three years later.

Do visitor spaces need charge points?

Visitor spaces inside the site boundary count as associated parking spaces. They do not push the charge point count above the number of dwellings, but they can trigger cable routes once the site passes 10 associated spaces.

Does Part S apply to a single self-build home?

Yes, where it is a new residential building with associated parking. One charge point per dwelling with a parking space, meeting the same technical standard as any other new home.

Are there any exemptions for new homes?

Where associated parking is in a covered car park, the requirement to install charge points does not apply to those spaces. Cable routes must be installed instead.

A covered car park is any car park enclosed by a roof. Garages and carports serving a single dwelling are excluded, as are carports that simply cover open spaces.

This matters because a large share of urban apartment parking is undercroft, podium or basement. Residents in those buildings often end up moving in with no way to charge at home.

Developers can still install charge points in covered car parks. Part S is a minimum, and local planning rules or sales ambitions often justify going further.

Guidance for conversions, renovations and commercial buildings (S2–S6)

Are there any exemptions?

Listed buildings, conservation areas and scheduled monuments can be exempt from the conversion requirement where compliance would unacceptably alter their character. Cladding remediation work is also outside Part S. On renovations, if charge points plus cable routes would cost more than 7% of the total capital cost, cable routes alone will do. If cable routes alone exceed 7%, neither is required.

What is the £3,600 connection cost cap?

For new residential buildings, the number of charge points required is the maximum you can install at an average connection cost of £3,600 or less per charge point. Connection cost is the extra cost of the incoming electrical supply compared with the same building without charge points. It excludes VAT, building work and the charge points themselves.

To evidence it, our advice is to give your building control body at least two formal quotes at notice or plans stage, with at least one from a distribution network operator (DNO). They should show total connection costs with and without charge points, the average additional cost per charge point, and the maximum number that fits under the cap. Where several dwellings share the same notice or plans, you can average the cost across them.

Hitting the cap doesn't end your obligations. Cable routes must still go into every space that would otherwise have had a charge point.

What are the technical requirements for Part S charge points and cable routes?

A Part S charge point must have:

• A minimum rated output of 7kW

• Design and installation to BS EN 61851

• A Mode 3 system on a dedicated circuit

• A universal untethered socket (tethered units are allowed, but you can't know a new owner's vehicle will be compatible)

• A charging status indicator, using lights or a display

• Compliance with BS 7671 and the IET Code of Practice for EV charging equipment installation

The Electric Vehicles Smart Charge Points Regulations 2021 apply, so the charger must also be smart. To be smart, the charger must comply with a list of requirements, including being able to send and receive data and automatically adjust when and how fast it charges to protect the grid.

One charge point can serve more than one space, as long as every served space can charge at the same time. In practice that means a unit with multiple outlets, each meeting the full technical standard.

Who signs off Part S compliance, and what if you don't comply?

Your building control body signs it off, either local authority building control or a registered building control approver. Present any exemption evidence at notice or plans stage, not at completion.

Installing a charge point in a dwelling is also electrical work under Part P, so it must be done by an installer registered with a competent person scheme, or be notified to building control.

Contraventions can be prosecuted by the local authority in the magistrates court. The more common commercial consequence is a held up completion, or a retrofit bill landing on a building that was signed off with ducting only.

Does local planning policy override Part S?

Local planning policy doesn't override Part S. Design to Part S, not the local plan minimum, and check whether your local plan raises the bar higher.

Get Part S right before you build

Part S sets the minimum. What buyers notice is whether they can charge at home when they move in. Get an EV specialist to help get the design right early and you can meet the regulations, avoid over-specifying power, and hand over homes where the charger works. In our experience, that’s much cheaper to plan in than to retrofit.