As solar PV installations accelerate across the UK, concerns are growing over associated fire risks. Kevin Taylor, Training & Technical Support Manager at Marley, examines the dangers of poor installation practices, the importance of correctly tested and certified systems, and what roofing contractors need to know to protect buildings and occupants.
The drive to decarbonise the UK’s housing stock continues to intensify in the face of soaring energy costs, environmental considerations and ever-tightening regulation such as the Future Homes Standard and the Building Regulations.
This, in turn, is fuelling the widespread installation of solar photovoltaic (PV) panels onto both new and existing homes. Recent figures published by the Government reveal that more than 170,000 solar panel installations took place to the end of July this year alone, taking total installations across the UK beyond the two million mark.
However, solar installations must do more than generate energy. As with other components used in construction, they must protect occupants and the overall building fabric, giving both building owners and users the confidence that the installation is a safe one.
However, fires emanating from PV solar panels are a burgeoning area of concern, with research showing that these are growing much faster than the rate of installations, with an increase of 133% between 2022 and 2025.
Even if it were needed, this is a clear reminder to all parties to ensure solar installations protect as far as possible against the risk of fire. Contractors must ensure the chosen system has been correctly tested and certified for its intended application and is installed according to the manufacturer’s guidelines and overall best practice.
The risks of poor practice
Installation of a solar PV system, which is later found to be unsafe, has the potential to result in severe consequences for contractors. Solar installations combine high-risk activities, such as working at height and handling dangerous live DC voltages, meaning substandard or dangerous work is proactively policed by regulators.
Most reputable UK installers rely on the Microgeneration Certification Scheme (MCS)and NICEIC accreditations. An unsafe installation will automatically trigger an investigation, with proven non-compliance or dangerous shortcuts typically resulting in the immediate suspension or stripping of MCS status. Without this, contractors cannot issue the certificates occupiers need to sell electricity back to the grid, potentially damaging both their reputation and their ability to win future contracts.
If an installer knowingly violates technical regulations, their professional indemnity and public liability insurance providers may void the policy. Where a system causes an electrical fire or roof collapse, the client’s insurer may seek to recover damages, at significant cost to the contractor.
What contractors need to know
This makes knowledge of the fire risks and measures to mitigate them critical for solar PV installers.
DC connections present a significant risk. Incorrect connections or the cross-mating of connectors can cause electrical arcs, potentially spreading fire behind panels and into roof spaces. The compatibility and fire performance of panels, mounting systems, flashings and associated components as a complete system must therefore be considered.
For roof-integrated systems, MCS certification also specifically requires the mounting system to be used with modules specifically listed on its MCS 012 certificate and having the appropriate fire classification for that mounting kit.
It is also worth remembering that certification of individual components does not automatically ensure they have been tested and certified in combination. This means using a system which has been tested and certified in unison is always a sensible option.
A truly safe system
One such system is the Marley SolarTile roof-integrated solar system, which achieves a high classification for resistance to the spread of flame and fire penetration in European fire safety tests (BRoof T1, T2, T3 and T4). This is supported by independently verified BBA Solar System certification covering the solar panels, solar flashings and their combined system.
ArcBox.
The system also includes ArcBox, which is designed to enclose a DC connector and contain an electrical arc, helping to prevent its spread to combustible materials around the installation.
As solar deployment accelerates, safety must remain central in every installation. Installers who can supply and guarantee compliant installation of systems accredited to the highest safety standards will provide peace of mind for their customers, and so position themselves best to win further contracts.
Find out more on Marley’s website.