If you already have manual driveway gates and you want them to open automatically, the answer is almost always yes. Automating an existing gate is one of the most cost-effective upgrades a London homeowner can make because you are paying for the motor and the installation labour rather than for a new gate, new posts, and groundworks on top.
This guide explains the four things a site survey assesses to determine whether your gates are suitable for automation, what the retrofit costs, which motor type suits which installation, and what the process looks like from first call to completion.
Why Retrofit Rather Than Replace
The case for retrofitting automation to existing gates rather than replacing with a new electric gate is straightforward when the existing gates are in good structural condition.
A new electric gate installation covers the cost of gate fabrication or supply, post foundations, groundworks, motor, safety devices, electrical connection, and commissioning. Depending on specification, this runs from £4,500 to £14,000 for a residential installation in London.
A retrofit covers the motor, safety devices, electrical connection, and commissioning only. The gate and posts are already there. A standard retrofit in London runs from £1,500 to £3,500.
The quality of the result is comparable. A well-specified retrofit on sound existing gates produces a gate that operates as reliably as a new installation. The motor does not know whether the gate it is attached to is new or ten years old, provided the gate is mechanically sound and correctly hung.
The exception is when the existing gates are genuinely not suitable for automation, in which case replacement is the more cost-effective long-term decision. The site survey establishes this clearly.
For a full comparison of electric and manual gate options, see our electric vs manual gates guide.
The Four Assessments That Determine Suitability
Assessment 1, Gate Weight and Structural Condition
Every motor system has a maximum gate weight it is rated to operate. Residential swing gate motors are typically rated for single leaves of 300kg to 500kg depending on the motor specification. Most standard residential steel or timber gates are well within this range.
The structural condition of the gate matters more than the weight. A gate that has developed frame distortion, has loose or corroded welds, or has significant rust at the hinge points will transmit those structural weaknesses into accelerated motor wear. A gate in poor structural condition that is automated will develop motor problems within a year or two as the motor compensates for the gate’s mechanical failings on every cycle.
We assess gate condition during the site survey. In cases where the gate is borderline, we give a clear recommendation on whether repair is worthwhile or whether new fabrication is the better investment.
Assessment 2, Hinge Condition and Gate Geometry
The gate must swing freely and smoothly by hand before a motor is fitted. This sounds obvious but it is the most frequently overlooked assessment on DIY retrofits. A gate that sticks at one point in its travel arc, requires a push to get started, or has a hinge that has worn and dropped the gate leaf out of plumb will work harder than its rated load on every cycle.
We check hinge condition, gate plumb and alignment, and confirm that the gate travels cleanly through its full arc without binding. Where hinges are worn, we replace them as part of the retrofit rather than fitting a motor to a gate that will immediately stress it.
Assessment 3, Post Foundation Stability
The gate posts take the combined load of the gate weight, wind loading, and the motor’s operational force. In London clay, post foundations can shift subtly over years without the movement being obvious above ground. A post that looks perfectly vertical may have a foundation that has moved 15mm to 20mm due to seasonal clay expansion and contraction.
This matters for automation because the motor is fixed to both the gate leaf and the post. If the post moves seasonally, the motor geometry changes and the system can develop fault conditions. We assess post stability at the survey by checking plumb at multiple heights and, where there is any doubt, by probing around the post base.
For detailed guidance on existing post and pier assessments, see our guide to electric gates with existing brick piers.
Assessment 4, Electrical Access and Cable Route
The motor needs a power supply, which means a cable route from the consumer unit inside the house to the gate post at the road boundary. On most London residential properties this involves running a cable under a path, through or alongside a boundary wall, and into a conduit at the post base.
We assess the cable route at every survey because this is the element with the most site-specific variation in cost. A straightforward route over 8 metres of path under a gravel surface costs significantly less than a 25-metre route requiring trenching under established block paving with surface reinstatement. We quote this separately so the cost is transparent.
Motor Types for Retrofit Installations
Ram-Arm Motors
Ram-arm motors are the standard specification for most London residential retrofits. They mount on the rear face of the gate post and the rear face of the gate leaf, with an articulated arm connecting the two. When the motor operates, the arm pushes or pulls the gate through its arc.
Ram-arm motors are visible when the gate is open, but are hidden behind the gate leaf when closed, making them effectively invisible from the street in the closed position. They are robust, reliable, and straightforward to install on most existing gate configurations. Ram-arm retrofit pairs in London cost between £1,500 and £2,500 fully installed including safety devices and commissioning.
Underground Motors
Underground motors are mounted beneath the gate post cap, with the motor housing excavated into the ground at the post base. The gate leaf connects to the motor via a drive arm that emerges from the ground. When the gate is closed, there is no visible mechanical component on the post face.
Underground motors are the premium retrofit specification and are popular on period properties in Wimbledon Village, Richmond Hill, Kew Green, Twickenham, and Esher where the visual standard of the entrance requires a completely clean post face. They cost more to install than ram-arm motors and require excavation at the post base, which is not always practical on existing installations with established paving or drainage at the post.
Underground retrofit pairs in London cost between £2,500 and £4,500 fully installed.
Smart Gate Integration
Any motor can be connected to a smart gate system with app control and video intercom. CAME Connect integration allows the gate to be operated from anywhere in the world via smartphone, with activity logging, visitor access management, and real-time notifications. Adding smart integration to a retrofit costs approximately £600 to £1,200 more than a basic remote-only setup.
See our smart gates page for the full CAME Connect feature set.
Retrofit Costs in London 2026
| Retrofit Specification | Typical Installed Cost in London |
| Ram-arm motors (pair), photocells, remotes | £1,500 to £2,500 |
| Ram-arm motors (pair) with video intercom | £2,000 to £3,000 |
| Underground motors (pair), photocells, remotes | £2,500 to £4,500 |
| Underground motors (pair) with video intercom | £3,000 to £5,000 |
| Smart gate app integration added to any above | Add £600 to £1,200 |
These figures include motor supply, safety devices (photocells, safety edges, control board), electrical connection, programming, commissioning and EN 12453 safety compliance documentation. They assume a cable route of up to 15 metres without major groundwork disruption. Longer cable runs or routes requiring extensive excavation under established hard landscaping are quoted separately.
For a full cost comparison with new electric gate installations, see our driveway gates cost guide.
What the Retrofit Process Looks Like
Site survey. We visit the property, assess the gate condition across the four criteria above, measure the cable route, discuss motor type and access control preferences, and provide a written quote. The survey takes 45 to 60 minutes and is free with no obligation.
Fabrication and ordering. Once the quote is accepted, the motor system is ordered. CAME motors are typically available within one to two weeks.
Installation day. A standard retrofit on a pair of swing gates takes one day. We dig the cable trench, run conduit and cable from the consumer unit to the post, fit the motors, connect the control board, install photocells and safety edges, fit the intercom if specified, programme remotes, and carry out commissioning.
Commissioning and handover. Force testing is carried out with calibrated equipment to confirm the gate meets EN 12453 safety requirements. All documentation including Declaration of Conformity, force test results, and user instructions are provided at handover. The manual release is demonstrated before we leave.
Sloped Driveways and Retrofit
A sloped driveway changes the retrofit specification in the same way it changes a new installation. If the driveway slopes significantly toward or away from the road, swing gate automation may not produce an acceptable result and a sliding gate conversion may be the better option. See our sloped driveway guide for the full framework.
Safety Requirements Apply to Retrofits
A retrofit installation carries the same legal safety requirements as a new electric gate installation. Under HSE guidelines for powered gate installations, all electric gates, including retrofitted manual gates, must include safety photocells, safety edges, force compliance testing, and manual release documentation. These are not optional and cannot be waived because the gate pre-existed the motor.
Every NOVA Gates & Railings retrofit includes full EN 12453 compliance documentation at handover.
About NOVA Gates & Railings
NOVA Gates & Railings is a CAME approved bespoke gate installer based in Wimbledon, carrying out gate automation retrofits and new electric gate installations across South West London and Surrey.
We cover SW19, SW20, SW15, SW18, SW4, SW6, SW11, SW17, SW3, TW9, TW10, TW1, TW2, TW11, KT1, KT2, KT10, KT17, SM1, SM2 and surrounding areas.
Book a Free Site Survey
Call us on 020 7117 2642 or get in touch to arrange a free site survey.
NOVA Gates & Railings. Gate Automation Retrofits. Wimbledon, London and Surrey. CAME Approved. 10-Year Warranty.
Frequently Asked Questions
Can I add automation to my existing manual gates?
In most cases yes, provided the gates are structurally sound, correctly hung, and within the weight and geometry range suitable for the motor system. A site survey confirms whether your specific gates are suitable.
How much does it cost to automate existing gates in London?
A standard retrofit on a pair of existing swing gates in London costs between £1,500 and £3,500 fully installed depending on motor type, gate weight, and whether additional access control is included.
Do I need planning permission to add automation to existing gates?
No, in most cases. Adding a motor to existing gates does not alter the gate’s height or position, so permitted development rights apply. Exceptions: listed buildings and certain conservation area Article 4 Directions.
How long does a gate automation retrofit take?
A standard retrofit on a pair of swing gates, including motors, photocells, control board, intercom, and remotes, is typically completed in one day.
Is retrofit cheaper than replacing with new electric gates?
Yes, significantly. You avoid the cost of gate fabrication, new posts, and groundworks. A retrofit starts from around £1,500. A complete new electric gate installation starts from around £4,500.
