EV Charging Site Surveys: What to Expect Before Installation
Every successful EV charger installation starts with a thorough site survey. Whether you are a homeowner fitting a single charger or a commercial property owner planning a twenty-unit installation, the site survey determines what is possible, what it will cost and how long it will take. Skipping or rushing this step is the single most common cause of installation delays, unexpected costs and underperforming charging systems.
This guide explains what a professional EV charging site survey involves, what the surveyor is looking for, how to prepare for one, and what the survey report should tell you.
Why the Site Survey Matters
An EV charger draws significant electrical load. A single 7 kW home charger draws roughly the same current as an electric shower. A commercial installation with ten 22 kW chargers draws more power than most of the other equipment in the building combined. Understanding your electrical infrastructure before committing to an installation is not optional — it is essential.
The site survey answers three fundamental questions: Can your existing electrical supply support the chargers you want? Where is the most practical and cost-effective location to install them? What additional work is needed to make the installation safe, compliant and fit for purpose?
Without these answers, you are guessing — and guessing leads to mid-project surprises, budget overruns and installations that do not meet your needs.
What the Surveyor Inspects
Incoming Electrical Supply
The first and most important assessment. The surveyor will identify your supply type (single-phase or three-phase), rated capacity (measured in amps), and current condition. They will record the main fuse or cut-out rating and check for any supply limitations imposed by the DNO.
For residential properties in Manchester, a typical supply is 100 A single-phase. For commercial properties, it varies enormously — from 60 A single-phase for a small shop unit to several hundred amps three-phase for a large commercial building.
The supply capacity determines how many chargers can be installed without requiring a DNO upgrade. This single factor has the greatest impact on project cost and timeline.
Consumer Unit or Distribution Board
The surveyor examines your main electrical panel to assess spare capacity for additional circuits, the age and condition of the board, whether RCD protection is present and adequate, the suitability of existing protection devices, and whether the board meets current BS 7671 standards.
For home installations, a consumer unit with no spare ways means either a board upgrade or an additional board to accommodate the new EV charger circuit. For commercial properties, the distribution board assessment is more complex, often involving multiple sub-boards and three-phase distribution.
If your consumer unit is an older rewireable fuse board or does not have RCD protection, it will need replacing before or as part of the EV charger installation. This is a safety requirement, not an optional upgrade.
Cable Routing
The surveyor traces the most practical route for cables from the distribution board to the proposed charger location. They are looking at the total cable run distance (which determines cable size and cost), whether the route is internal, external or both, any obstacles such as walls, floors, ceilings or external ground that need penetrating, fire-rated zones that require fire-rated cabling or fire stopping, and access points for future maintenance.
For home installations, the cable route is usually straightforward — through the garage, along the outside wall or through the loft. For commercial properties, cable routing can be the most complex part of the project, involving underground trenching across car parks, containment systems along building exteriors and multiple fire barrier penetrations.
Proposed Charger Location
The physical location where the charger will be mounted needs to meet several criteria. The wall or post must be structurally sound enough to support the charger's weight (typically 5 to 15 kg). The charger must be positioned at an accessible height (typically 0.75 to 1.2 metres to the socket or connector). There must be adequate clearance for the charging cable to reach the vehicle. The location must be protected from mechanical damage from vehicles. Drainage and water management must prevent standing water around the charger.
For commercial installations, the surveyor also assesses bay layout, traffic flow, pedestrian routes, lighting and signage requirements.
Earthing and Bonding
Proper earthing is critical for electrical safety. The surveyor checks the earthing system type (TN-S, TN-C-S or TT), earth electrode condition and resistance (for TT systems), main bonding connections, and supplementary bonding where required.
EV chargers require specific earthing arrangements. If the existing earthing system is inadequate, additional earthing work is needed before installation. Properties with TT earthing systems — common in rural areas around Greater Manchester — may need an earth rod installed specifically for the EV charger circuit.
Existing Electrical Load
The surveyor needs to understand how much of your current electrical supply is already being used. For residential properties, this is relatively simple — lighting, heating, cooking and other domestic appliances rarely exceed 40 to 60 per cent of the available supply.
For commercial properties, the existing load assessment is more detailed. The surveyor may need to review maximum demand data from your electricity supplier, inspect metering records, or install temporary monitoring equipment to measure actual demand patterns over a representative period.
This data determines how much spare capacity is available for EV charging and whether load management systems could help maximise charger numbers without a supply upgrade.
External Factors
The surveyor also considers factors outside the building: access for delivery and installation vehicles, parking restrictions during installation, proximity to the DNO service cable and meter position, any wayleave or easement requirements for cable routing across third-party land, and planning permission requirements for external structures or significant visual changes.
The Survey Report
A professional survey report should provide clear, actionable information. At minimum, it should include:
Existing supply summary — Type, capacity, condition and spare capacity assessment.
Proposed installation specification — Charger type, quantity, location, cable sizes, protection devices and containment method.
Load assessment — Existing demand, proposed additional demand and whether load management is recommended.
DNO requirements — Whether a supply upgrade or notification is needed, estimated cost and timeline.
Cost estimate — Itemised breakdown of all costs including hardware, labour, materials, any required upgrades, groundwork and certification.
Timeline — Realistic installation schedule including lead times for any DNO work or equipment procurement.
Photographs — Annotated photos of the incoming supply, distribution board, proposed cable routes and charger locations.
Red Flags in a Survey Report
Be cautious of survey reports that lack detail on your existing electrical supply capacity, do not mention load assessment or spare capacity, give a single headline price without itemisation, do not address DNO requirements, or fail to mention certification and testing on completion.
A thorough survey takes time. For a residential property, expect 30 to 60 minutes on site. For a commercial property with multiple proposed charger locations, allow two to four hours.
How to Prepare for Your Site Survey
You can help the survey go smoothly and ensure nothing is missed by having the following ready:
For homeowners: Access to your consumer unit and electricity meter. Any existing electrical certificates (EICR, installation certificate). Knowledge of where you want the charger located and which side of the car the charge port is on.
For commercial property owners: Access to all distribution boards and electrical intake rooms. Recent EICR or fixed wire test report. Any electrical schematics or layout drawings. Maximum demand data from your electricity supplier if available. Car park layout plan showing proposed charger locations. Information on any planned building changes or expansions.
For multi-unit residential: Communal area access arrangements. Freeholder or management company approval in principle. Information on existing communal electrical supply. Parking space allocation plan.
What Happens After the Survey
Following the survey, you should receive a detailed report and quotation within three to five working days. For straightforward residential installations, some companies provide same-day quotations.
If a DNO supply upgrade is needed, the application process starts as a separate workstream. Your installer should handle the DNO application on your behalf — this involves submitting technical details of the proposed installation, receiving a connection offer from Electricity North West, accepting the offer and paying any required contribution, and waiting for the upgrade works to be completed (typically 8 to 16 weeks).
If no supply upgrade is needed, most residential installations can be completed within one to two weeks of survey approval. Commercial installations typically require two to six weeks depending on scale and complexity.
Manchester-Specific Survey Considerations
Properties across Greater Manchester present some recurring survey challenges:
Victorian and Edwardian terraces — Common in areas such as Levenshulme, Chorlton, Didsbury and Salford. These properties often have consumer units in awkward locations (under stairs, in cellars) with limited spare capacity and outdated earthing systems. Cable routing to an external charger can require careful planning to avoid visual impact on period frontages.
Ex-council properties — Common across Tameside, Oldham and Rochdale. Often have TT earthing systems requiring additional earth electrodes. Some have communal electrical supplies that complicate individual charger installations.
New build estates — Properties built since 2022 should have pre-installed cable routes for EV chargers under Building Regulations Part S. The survey for these properties is usually simpler and the installation cost lower.
Commercial units on industrial estates — Often have generous three-phase supplies with good spare capacity. However, the distance from the distribution board to parking areas can be significant, adding cable cost.
Booking Your Survey
At Manchester Compliance, we offer free EV charging site surveys for properties across Greater Manchester. Our surveys are carried out by qualified electricians experienced in EV charger installations — not salespeople with a clipboard. You receive a detailed technical report and a fixed-price quotation with no hidden costs.
Call 0161-XXX-XXXX to book your free site survey, or email hello@manchestercompliance.co.uk. Same-week survey appointments are available for most Greater Manchester locations.