If you are planning an EV charger installation in Surrey, you may expect the work to be straightforward: choose a charger, arrange an installation date and start charging at home.
For many properties, that is exactly what happens. However, some older homes in Redhill and the surrounding area have a looped or shared electricity supply. This is particularly common in older terraces and semi-detached properties around Earlswood, St John’s, Linkfield, Merstham and Salfords, as well as some Reigate and Horley terraces and 1970s and 1980s housing estates.
A looped supply is one of the most common reasons an EV charger installation is delayed, redesigned or referred to the local Distribution Network Operator (DNO).
What is a looped electricity supply?
A looped supply is where the incoming electricity service cable is shared between two properties.
Instead of each home having a completely separate service cable from the local network, one supply may enter the first property and then continue or “loop” through to a neighbouring property. This arrangement was commonly used when streets were originally developed because it reduced installation costs and simplified the network layout.
The arrangement is not automatically unsafe. Your home may have operated perfectly well for decades. The issue is that a typical 7kW EV charger draws around 32 amps when charging. Adding that sustained load to a shared service cable could exceed the capacity allowed by the DNO or affect the supply available to the neighbouring property.
That is why a standard charger installation cannot simply be connected without checking the supply first.
How can you tell if your home has a looped supply?
Most homeowners cannot confirm a looped supply from the electricity meter alone. There are, however, several clues:
- Your property is an older terrace or semi-detached home.
- The incoming service cable appears to continue towards a neighbouring property.
- Your electrician identifies two service cables or an unusual arrangement at the service head.
- A previous electrical report, DNO record or neighbour’s installation refers to a shared supply.
- The property is part of an older estate where homes were built with shared network connections.
Do not remove seals, open the DNO service head or interfere with the incoming supply yourself. The safest approach is to ask a qualified electrician to inspect the installation during a site survey. The DNO may also need to confirm the arrangement from its network records.
A looped supply is not the same thing as two homes sharing a meter or having a communal landlord supply. Flats, converted buildings and properties with private shared electrical infrastructure may require a different connection solution.
Why does a looped supply affect a standard 7kW charger?
A standard home charger is usually connected as a dedicated 32A circuit. Although the charger may not draw its full rating continuously, the installation must be designed for its maximum demand.
On a non-looped supply with adequate capacity, the electrician can normally assess the installation, fit the charger and notify the DNO after completion. This is often described by installers and homeowners as the usual “G98 notify-after” route.
Strictly speaking, G98 relates to small-scale electricity generation, such as solar PV, rather than an EV charger that consumes electricity. For EV chargepoints, the relevant DNO connection and notification process is generally dealt with through the DNO’s low-carbon technology procedures, including G100 requirements where applicable. The important practical distinction is:
- Adequate, straightforward supply: install and notify the DNO after completion.
- Looped, shared or capacity-constrained supply: obtain DNO approval before installation.
If the supply is looped, the DNO needs to assess the shared cable, local network capacity and protective equipment. It may decide that the supply must be unlooped, also called de-looped, before the charger can be energised.
A charger should not be connected first and approved later simply because the property owner wants to avoid a delay.
What happens during the DNO prior-approval process?
A competent installer will collect the technical information required for the application and submit it to the relevant DNO. This normally includes:
- The property address and supply details.
- The main fuse rating.
- The proposed charger rating.
- The total maximum demand at the property.
- Details of the earthing arrangement and protective devices.
- Whether the supply is looped or shared.
- The proposed load-management or PEN fault protection arrangements.
The DNO may approve the installation as proposed, request a reduced charge rate or smart load-management system, or require the supply to be unlooped.
Unlooping usually involves separating the two properties so each has its own service arrangement. The DNO may need to coordinate with the neighbour, arrange street or pavement works and complete cable or service-head alterations.
An 8–12 week lead time is a realistic planning assumption for many unlooping projects. Some simpler jobs may be completed sooner, while difficult access, permissions, excavation and reinstatement can make the process longer.
How much does unlooping cost?
The cost depends on who carries out the work and what is included. Standard EV-related unlooping may be completed by the DNO without a direct charge to the homeowner, but this should never be assumed without checking the DNO’s written proposal.
Internal work, non-standard connections, meter relocation, private trenching or additional capacity upgrades may be chargeable.
The figures below are intended as a planning guide only:
| Work or option | Typical cost guide | Typical timeframe |
|---|---|---|
| Standard EV charger installation | £895–£1,250 supplied and fitted | 3–4 hours |
| Consumer unit upgrade | £200–£500 | Same day in many cases |
| Small dedicated consumer unit for charger | Site-specific | Usually part of installation |
| DNO assessment and approval | Varies; often handled by installer | Several days to several weeks |
| Standard supply unlooping | Often no direct homeowner charge, subject to DNO terms | Around 8–12 weeks |
| Chargeable or complex network works | Approximately £2,000–£4,000+, potentially more | Several weeks to several months |
The underlying cost of network unlooping can be several thousand pounds, but the amount paid directly by a homeowner depends on the DNO’s current policy and whether the work qualifies as an EV or low-carbon technology connection.
Ask for a clear breakdown of any DNO quote. Check whether it covers only unlooping or also includes extra work such as moving the meter, digging across private land or upgrading the supply.
What will an NICEIC Approved Contractor check?
A proper site survey is more than measuring the distance between the consumer unit and the driveway. An NICEIC Approved Contractor should assess the complete electrical installation, including:
Main fuse rating
The electrician will check whether the property has a 60A, 80A, 100A or another main fuse rating. A lower-rated or older supply may not have sufficient capacity for a 7kW charger alongside existing household demand.
Supply type
The earthing arrangement may be:
- TN-S
- TN-C-S, often referred to as PME
- TT
The supply type affects how the EV circuit must be protected, particularly where there is a risk of an open PEN conductor fault.
PEN fault protection
Many UK homes have a TN-C-S or PME supply. In this arrangement, a fault affecting the combined protective earth and neutral conductor could create a dangerous voltage on exposed metalwork.
For an EV charger, the installer must provide suitable protection in accordance with BS 7671 Section 722. Depending on the charger and the property, this may involve:
- A charger with compliant built-in PEN fault detection.
- A separate protective device.
- A dedicated TT earth arrangement and earth electrode.
- Appropriate RCD and DC residual-current protection.
The correct solution depends on the equipment, installation design and test results. It should not be selected solely by looking at the charger price.
Consumer unit and cable route
The electrician will also check for spare capacity, RCD protection, surge protection where required, cable sizing, isolation and the proposed route to the charger. If the existing consumer unit is outdated, a replacement or a small dedicated consumer unit may be recommended.
What are the alternatives while you wait?
If the DNO cannot approve a full 7kW charger immediately, there may be practical interim options.
Smart load management
A compatible charger can monitor the property’s demand and reduce its output when the oven, shower, heating or other high-load equipment is operating. This can help prevent the property’s total demand from exceeding an agreed limit.
Load management does not automatically remove the need for DNO approval on a looped supply. The DNO must accept the proposed design.
Reduced charge rate
Some chargers can be configured below their maximum output. Charging at 16A or another reduced rate may be suitable where the household supply is limited.
This will increase charging time, and it may still require prior DNO approval if the supply is shared.
A dedicated small consumer unit
A small consumer unit dedicated to the EV charger can be a neat solution where the main consumer unit has no spare ways or needs to remain untouched. It improves circuit separation and protection but does not, by itself, solve an external network capacity problem.
Advice for homeowners, landlords and businesses
Homeowners should arrange an electrical survey before purchasing a charger. Finding a looped supply early prevents disappointment and makes it easier to plan around the DNO timetable.
Landlords should check the supply before advertising an EV charging facility to tenants. Permission may be required for work affecting a shared service, communal area or neighbouring property. An up-to-date EICR and clear records of the charger installation should also be retained.
Businesses, offices and landlords with multiple parking spaces need a wider load assessment. Two or more chargers, electric heating, heat pumps, machinery or future expansion may require load balancing, a larger supply or three-phase power. ADS Electrical can coordinate the electrical design, DNO paperwork and other trades as part of a managed project.
Why use ADS Electrical for EV charger installation in Redhill?
ADS Electrical provides EV charging solutions Redhill and across Surrey for homes, landlords and businesses.
As a NICEIC Approved Contractor, we carry out a free site survey to identify supply restrictions, earthing requirements, consumer unit issues and cable-routing options before providing a price. We can provide a fixed-price quote within 24 hours for suitable projects, with standard installations typically completed in 3–4 hours.
Our service includes:
- EV charger supply and installation from £895–£1,250.
- Consumer unit upgrades from approximately £200–£500 where required.
- Main fuse, supply type and looped-supply checks.
- DNO notification and prior-approval applications.
- Unlooping paperwork handled on the customer’s behalf.
- Testing, certification and customer handover.
- Load-management and reduced-rate charging options where appropriate.
For more information, see our guide to home charging point Surrey installations.
Arrange your free site survey
A looped supply does not necessarily mean you cannot install an EV charger. It simply means the installation needs the correct assessment and, in some cases, DNO approval before work can proceed.
If you live in Redhill, Reigate, Horley, Earlswood, St John’s, Linkfield, Merstham, Salfords or the surrounding Surrey areas, call ADS Electrical on 07870 554498 to arrange a free site survey and discuss your EV charging requirements.