Workplace and Commercial EV Charging Installation: A Practical Guide for UK Businesses

Workplace electric vehicle (EV) charging has moved from a nice-to-have to an expectation. Fleets are electrifying, staff want to charge while at work, and new buildings must include charging infrastructure under the Building Regulations. But a charger is not just an appliance on a wall. It is a high, sustained electrical load, often outdoors, used by the public or staff, and subject to specific wiring rules, smart-charging legislation and fire safety considerations.

This guide is for facilities managers, business owners and estates teams planning commercial EV charging. It explains the decisions to make, the regulations that apply and how to avoid the common mistakes that add cost and delay.

Start with the use case, not the charger

The most expensive mistake is to buy chargers before understanding how they will be used. Ask:

• Who will charge? Fleet vehicles, staff cars, visitors or customers? Each has different patterns and different funding and regulatory implications.
• How long do vehicles stay? Staff parked for a full working day can be fully served by modest AC charging. Pool cars that turn around quickly, or delivery vans between shifts, may need faster charging.
• How many vehicles, now and later? Installing ducts and cable routes for future spaces during the first phase is far cheaper than digging up the car park twice.
• Who pays? Free charging, staff payment, or visitor payment all affect the back-office system you need.

Charger type	Typical power	Typical use	Points to consider
AC single-phase	Up to about 7 kW	Staff parking with long dwell times	Lowest cost per point; suitable for most workplace parking
AC three-phase	Up to about 22 kW	Fleet, pool cars, visitor parking	Needs a three-phase supply; not all vehicles can accept 22 kW AC
DC rapid	50 kW and above	Fleet turnaround, depots, public-facing sites	Significant supply capacity and cost; groundworks and transformer capacity may be needed

Supply capacity and load management

Every charger adds a large, sustained load, and several chargers running together can easily exceed the spare capacity of a building’s supply. Before committing to a design, a competent electrical contractor should assess:

• The capacity of the incoming supply and the building’s existing maximum demand, ideally using metered half-hourly data rather than estimates
• The condition and capacity of the main switchgear and distribution boards that will feed the chargers
• The earthing arrangement of the supply, which has a significant effect on design (see below)
• Routes for cables and ducts to parking bays, including any groundworks

Load management, which shares the available capacity between chargers and can respond to the building’s demand in real time, often allows more charge points without upgrading the supply. Where an upgrade is unavoidable, the lead time and cost from the network operator can be significant, so find out early.

The local Distribution Network Operator (DNO) must be notified of charge point installations, and larger installations may need approval before connection. Your installer should handle this as part of the project.

BS 7671 Section 722: the wiring rules for EV charging

EV charging installations must comply with BS 7671, the IET Wiring Regulations, and in particular Section 722, which deals specifically with EV charging. The IET’s Code of Practice for Electric Vehicle Charging Equipment Installation (5th edition) provides detailed guidance. BS 7671 Amendment 4:2026 was published in April 2026, so check that your design is to the current edition. The key Section 722 principles include:

Dedicated circuits

Each charging point should be supplied by its own dedicated final circuit, which must not supply other equipment.

RCD protection and DC fault currents

Each charging point must be protected by its own residual current device (RCD) with a rated residual operating current not exceeding 30 mA. Because vehicle charging can produce DC fault currents that blind a standard RCD, BS 7671 requires measures to protect against DC fault current. This is typically achieved with a Type B RCD, or with a Type A RCD together with equipment that disconnects the supply in the event of a DC fault current above 6 mA. Many modern charge points include this DC detection internally, but the designer must confirm it.

Earthing and the PME problem

Many UK supplies use a protective multiple earthing (PME) arrangement. If the combined neutral and earth conductor in the supply is broken, exposed metalwork connected to a PME earth can rise to a dangerous voltage. A vehicle being charged outdoors, with someone touching it while standing on the ground, is exactly the situation where this matters. BS 7671 therefore restricts using a PME earth for outdoor charging points unless specific measures are taken. Common solutions include a separate earth electrode so that the charge point is on a TT arrangement, or charge points with built-in devices that detect a broken PEN conductor and disconnect. The right solution depends on the site, and it is one of the most important design decisions.

External influences and protection

Outdoor equipment must be suitable for the environment: weather, impact from vehicles, vandalism and, in some locations, flooding. Bollards or wheel stops protect chargers and cables, and cable management should prevent trip hazards. For further background on recent changes to the wiring regulations, see our article on BS 7671 amendments.

Smart charging rules

The Electric Vehicles (Smart Charge Points) Regulations 2021 have applied since 30 June 2022 to private charge points sold in Great Britain for domestic or workplace use. According to the government’s guidance on the regulations, in-scope charge points must:

• Be able to send and receive information and respond to signals to change the rate or time of charging
• Keep their smart functions if the electricity supplier changes
• Continue to charge if the network connection is lost
• Include a measuring system for electricity consumed and charging time
• Be pre-set with default off-peak charging hours, which the owner can accept, remove or change
• Include a randomised delay function
• Meet security requirements in line with ETSI EN 303 645

Public charge points and rapid charge points are exempt. The regulations place duties mainly on sellers and manufacturers, but buyers should check that equipment is compliant and configure the default settings sensibly. For a workplace, the default off-peak hours may not suit daytime charging, so agree the configuration at commissioning.

Building Regulations Part S for new and renovated buildings

Part S of the Building Regulations, supported by Approved Document S, has applied in England since 2022. For new non-residential buildings, and for non-residential buildings undergoing major renovation, with more than ten parking spaces, the requirements are broadly:

• At least one charge point
• Cable routes for at least one in five of the remaining parking spaces
• Charge points with a minimum nominal rated output of 7 kW and an indicator showing charging status

There are exceptions and special rules, including for covered car parks and where costs exceed set limits on major renovations. Part S applies to building work, so existing car parks do not need to be retrofitted unless work triggers the requirements, but many organisations go further voluntarily. Your designer and building control body will confirm what applies to your project.

Fire safety and siting

EV fires are uncommon, but they behave differently from fires in petrol and diesel vehicles, and they can be difficult to extinguish. That matters most in covered and underground car parks. The Office for Zero Emission Vehicles published fire safety guidance for covered car parks in 2023, which has interim status while evidence develops. Practical considerations include:

• Update your fire risk assessment before installing chargers, not after
• Locate chargers away from escape routes, stair cores and building entrances where practicable
• Provide a clearly signed means of emergency isolation so the fire service can make chargers safe
• Consider whether detection, ventilation or suppression in the car park is adequate for the new risk
• Talk to your insurer early, because some policies include specific conditions for EV charging
• Engage with the local fire and rescue service on larger schemes

Accessibility also matters. The British Standards Institution’s PAS 1899 sets out guidance on accessible charge point design, including bay sizes, approach routes and the height of controls, which is particularly relevant to visitor and public-facing sites.

Funding and tax relief in 2026

Government chargepoint grants changed on 1 April 2026. According to the government’s summary of the changes and the Workplace Charging Scheme listing:

• The Workplace Charging Scheme remains open until 31 March 2027 for businesses, charities, public sector organisations and small accommodation businesses. It covers up to 75% of purchase and installation costs, capped at £500 per socket for installations completed on or after 1 April 2026, for up to 40 sockets across all sites.
• Applicants need dedicated off-street parking for staff or fleet use, and must use an authorised installer; the grant cannot be claimed otherwise.
• A separate version of the scheme for state-funded education institutions offers up to £2,000 per socket.
• The staff and fleets grant and the commercial landlord chargepoint grant closed to applications on 31 March 2026.

The 100% first-year capital allowance for EV charge points has also been extended to 31 March 2027 for Corporation Tax and 5 April 2027 for Income Tax. Take advice from your accountant on eligibility. Grant rules change frequently, so check the current position before you commit to a programme.

Commissioning, certification and ongoing maintenance

At completion you should receive an Electrical Installation Certificate for the work, evidence of DNO notification, equipment manuals and warranties, and details of the back-office and payment configuration. Make sure the new circuits are added to your distribution board schedules and asset register.

Charge points are heavily used outdoor equipment. A sensible maintenance regime includes:

• Regular visual checks of connectors, cables and housings for damage, especially on tethered units
• Functional testing of RCDs and DC fault protection as recommended by the manufacturer
• Firmware and software updates, which also matter for cyber security
• Including EV circuits in your periodic electrical inspection; see our EICR guide
• Thermal imaging of supply boards under load, which can spot overheating connections before they fail
• A clear process for reporting and fixing faults quickly, because a broken charger soon frustrates users

How JKS London can help

JKS London is an NICEIC-approved electrical and M&E contractor, established in 2004, working for commercial, public sector, airport and retirement living clients across London and the South East. We can assess your existing supply and distribution, design and install the electrical infrastructure to support charge points, upgrade switchgear, and add EV circuits to your planned maintenance and inspection programme. If you intend to claim the Workplace Charging Scheme grant, we will discuss with you at the outset how the authorised installer requirement applies to your project.

Find out more about our installations and refurbishment work and our services for commercial property, or contact us for a free, no-obligation site visit to discuss your plans.

Frequently asked questions