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Explore this serviceRC62 is the UK joint code of practice for fire safety on commercial rooftop solar PV, published by RISCAuthority with MCS and Solar Energy UK. Most solar panel fires start at poor DC connections or inverters, and insurers increasingly expect RC62 to be followed from design through to maintenance.
RC62, Recommendations for fire safety with PV panel installations, is the main UK guidance on reducing fire risk from rooftop solar PV. It is a joint code of practice published by RISCAuthority through the Fire Protection Association (FPA), produced with the Microgeneration Certification Scheme (MCS) and Solar Energy UK. The current edition (Version 2) was published in 2023, replacing the original document first issued in 2016, and is free to download from the FPA.
RC62 covers the whole life of a system, from procurement and design to installation, operation and maintenance, including retrofits and extensions. It is aimed at commercial and industrial rooftop arrays rather than homes, and it does not cover single dwellings, roof integrated PV, PV cladding or battery energy storage.
The document is written for the people who specify, design, supply, install, own and insure PV systems. For building owners, its main value is that it sets out what insurers and fire safety professionals now expect to see. It also asks owners to plan for the full 25 to 35 year life of an array, during which tree growth, nesting birds, new rooftop equipment and neighbouring construction can all change the original fire risk.
Solar panel fires remain rare relative to the number of installations, but they are increasing. Freedom of Information requests made by insurer QBE found that UK fire services attended 107 solar panel fires in 2022, 128 in 2023 and 171 in 2024. Over the same period the number of installations grew by around 30%, so fires rose roughly twice as fast as deployment. Only 37 of 49 fire services supplied data, so the true figures are likely to be higher.
Where the origin was recorded in 2024, the inverter and the panels themselves were the most common starting points, followed by DC cabling and battery banks. The growing use of lithium ion battery storage alongside PV is an emerging risk that RC62 does not address directly.
Most solar panel fires are electrical in origin. RC62 identifies poor installation as the largest single cause, followed by product failure, and cites a 2017 Building Research Establishment (BRE) study which found that DC connectors, inverters and DC isolators accounted for 84% of PV system fires. The main causes are:
The six minute video below summarises the main RC62 recommendations, and each one is explained in more detail in the sections that follow.
A suitable fire risk assessment, carried out and recorded by a competent person, is required under the Regulatory Reform (Fire Safety) Order 2005 and the Fire Safety Act 2021. RC62 recommends consulting the insurer and the local fire authority at an early stage, and confirming who owns both the building and the PV system, which is not always the same party. An emergency plan should be in place and rehearsed.
A new installation should not reduce the fire performance of the roof. RC62 recommends that PV arrays are installed on roofs constructed from non-combustible materials, classified A1 or A2 s1, d0 under BS EN 13501-1. A structural survey should confirm that the roof can carry the additional load, and ballasted systems need particular care because the gap under panels can trap debris and create hot spots.
Arrays and their cabling should not cross compartment walls or fire walls. RC62 sets out the separation between modules on either side of a fire wall:
| Situation | Minimum gap either side of the fire wall |
|---|---|
| Standard installation | 2.5m |
| Low risk of fire spread, with non-combustible roof elements and low spread panels | 1.2m |
The 1.2 m gap also applies to buildings adjoining town centre shops and offices, where a 2.5 m gap would make PV unworkable and fire spread between buildings is unlikely. Where cables must pass over a compartment wall, they should run in fire resistant ducts or shafts.
DC cable runs inside the building should be kept short, mechanically protected and mapped so that firefighters know where they are. Because panels continue to generate electricity in daylight even when the AC supply is isolated, RC62 describes measures that can make internal DC wiring safe, including a remote fire service switch and module level power electronics. Designers should also decide whether the inverter's built in arc fault protection is sufficient or whether a separate device is needed, and areas containing inverters should have automatic fire detection.
Firefighters need to know that PV is present and how to isolate it. RC62 recommends a "PV on the roof" sign of at least 100 mm by 100 mm at the consumer unit or supply cut-out, together with a site information pack showing the location of arrays, isolation points and fire alarm panels. Clear access routes should be maintained, and arrays should not be so densely packed that they restrict firefighting.
RC62 recommends that commercial systems are inspected at least once a year by a competent person, with maintenance carried out to BS EN IEC 62446-2:2020 and the manufacturer's requirements. A good maintenance regime includes:
Maintenance tasks can be scheduled through SFG20 so that they form part of the building's planned preventive maintenance programme.
PV projects fall under the Construction (Design and Management) Regulations 2015. RC62 recommends that installers hold, as a minimum, MCS certification for PV, ISO 9001 and SSIP registration, and that modules are MCS certified. Subcontractors should be checked as carefully as the main contractor, since they often carry out the highest risk work.
RC62 was written with insurers in mind, and Solar Energy UK recommends that the insurance industry uses it as the guide to fire risk prevention for UK solar systems. In practice, insurers increasingly ask whether a rooftop array has been designed, installed and maintained in line with RC62. Building owners planning a new array should speak to their insurer before the design is fixed, as retrofitting fire separation or isolation measures later is far more expensive.
In July 2025 the National Federation of Roofing Contractors and partner organisations, including Solar Energy UK, published a position paper on RC62. It argued for a more risk based interpretation for flat roofs, based on the performance of the whole roof system and test data rather than material classification alone. RISCAuthority agreed to revise RC62 in response. Until a revised edition is published, the 2023 edition remains the reference document, and designs should be checked against the latest version at the time of procurement.
A building services engineer can manage fire risk from the outset rather than leaving it to the installer. On a typical project this involves:
KJ Tait's engineers design and specify solar PV installations for commercial buildings across the UK, working with clients, insurers and contractors to apply RC62 from feasibility through to handover and maintenance.
Contact us to discuss a solar PV project.
RC62, Recommendations for fire safety with PV panel installations, is a joint code of practice published by RISCAuthority and the Fire Protection Association with MCS and Solar Energy UK. It sets out how commercial and industrial rooftop solar PV systems should be procured, designed, installed, operated and maintained to reduce the risk of fire.
RC62 is a RISCAuthority document published by the Fire Protection Association (FPA). The current edition was produced jointly with the Microgeneration Certification Scheme (MCS) and Solar Energy UK and published in 2023, replacing the original 2016 version.
RC62 is not law, and using it is voluntary. Within the document, "must" marks a compulsory procedure, "shall" a requirement that can only be departed from with a written risk assessment, and "should" recommended best practice. Building owners must still carry out a fire risk assessment under the Regulatory Reform (Fire Safety) Order 2005, and many insurers expect RC62 to be followed as a condition of cover.
No. RC62 is aimed at commercial and industrial rooftop systems. It does not cover single dwellings, roof integrated PV, PV cladding or battery storage, although many of its principles are good practice for any installation.
Freedom of Information data gathered by insurer QBE recorded 171 solar panel fires attended by UK fire services in 2024, up from 107 in 2022. Only 37 of 49 fire services supplied data, so the true number is likely to be higher. Fires rose roughly twice as fast as the number of installations over the same period.
RC62 recommends that commercial systems are inspected at least once a year by a competent person, with maintenance carried out to BS EN IEC 62446-2. Cleaning, thermographic surveys and electrical testing should be planned as part of the maintenance regime, and systems should also be checked after extreme weather.
In July 2025 the roofing industry, led by the National Federation of Roofing Contractors, published a position paper calling for a more risk based approach to flat roofs, and RISCAuthority agreed to revise RC62. Until a revised edition is published, the 2023 edition remains the reference document.
