Overview
SIST-TP CEN/TR 18326:2026 provides a comprehensive examination of installation scenarios, fire performance test methods, and national legislation relevant to the external fire performance classification of roof systems equipped with above-roof mounted photovoltaic (PV) modules. Developed by the SIST and stemming from work done within CEN/TC 127 on fire safety in buildings, this technical report primarily addresses Building Attached PV (BAPV) systems, reflecting their growing use across Europe.
The report offers a summary of current testing practices, guidance, and regulatory approaches. It includes an analysis of the responsibilities of various stakeholders involved in planning, installing, and maintaining PV installations, emphasizing the critical role of fire safety in the era of expanding renewable energy infrastructure.
Key Topics
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Installation Scenarios: The document reviews common BAPV mounting configurations, covering both flat and pitched roof installations. It highlights the significance of design parameters such as module distance from the roof, arrangement, orientation, and type of mounting structure, all of which can influence fire performance.
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Fire Performance Classification: It investigates the impact of PV modules on the external fire resistance of roofing systems. This includes a review of the applicable standards, like EN 13501-5 for classification and CEN/TS 1187 for test methods, noting the lack of harmonized European approaches for BAPV-roof combinations.
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Available Test Methods: The report describes current methods for assessing fire exposure and reaction, such as those outlined in IEC 61730, CLC/TR 50670, and ongoing national initiatives. It also outlines differences in assessment criteria, including the spread of flame and roof penetration resistance.
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National Legislation: A comparative overview of national regulations is provided, highlighting varying requirements on PV module placement, distances from roof penetrations and fire barriers, and the adoption of glass-backed modules or specific roofing systems for assurance.
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Stakeholder Responsibilities: The responsibilities of designers, installers, and operators are discussed, especially regarding regulatory compliance, ongoing maintenance, and risk mitigation.
Applications
SIST-TP CEN/TR 18326:2026 is a valuable resource for a range of users involved in PV and roofing industries, including:
- Architects and Designers: Guiding design decisions to ensure that the integration of PV modules meets relevant fire safety regulations.
- Installers and Contractors: Assisting with correct installation approaches, selection of mounting systems, and understanding national requirements to reduce fire risk.
- Product Manufacturers: Informing development of PV modules and mounting systems that comply with evolving fire performance standards.
- Regulatory Authorities: Aiding the creation and harmonization of fire safety standards and codes for roof-mounted PV systems.
- Insurance and Risk Assessors: Providing insight into best practices for minimizing fire-related incidents in buildings with BAPV systems.
This guidance is particularly important for large-scale or industrial PV installations, where rooftop fire spread could have severe consequences.
Related Standards
Key standards referenced and discussed within the report include:
- EN 13501-5: Fire classification of construction products and building elements – Part 5: Classification using data from external fire exposure to roofs tests.
- CEN/TS 1187: Test methods for the exposure of roofs to fire from outside.
- IEC 61730 Series: Photovoltaic (PV) module safety qualification (covering construction and testing).
- IEC 63027: DC arc detection and interruption in PV power systems.
- IEC 62446-2: Requirements for testing, documentation, and maintenance of grid-connected PV systems.
- CLC/TR 50670: External fire exposure to roofs in combination with photovoltaic arrays – Test method(s).
National guidelines and specifications from countries like France, the Netherlands, Italy, and Slovenia are also referenced, demonstrating the diverse landscape of fire safety regulation for above-roof PV systems.
Keywords: fire performance of PV modules, above roof mounted PV, roof system fire safety, fire resistance classification, BAPV fire risk, photovoltaic installation standards, external fire exposure testing, national building regulations for PV roofs.