Overview
CEN/TR 18326:2026 is a technical report developed by CEN/TC 127 focusing on the fire performance classification of roof systems with above roof mounted photovoltaic (PV) modules. With the growing adoption of solar energy and the increasing number of roof-mounted PV installations across Europe, there is a strong need for harmonized guidance on how to assess and improve the external fire safety of roofs with PV modules. This standard provides a comprehensive review of relevant installation scenarios, available fire test methods, and national legislations affecting both planning and maintenance of above-roof PV systems. The report also identifies current stakeholders and examines their responsibilities throughout the lifecycle of PV installations.
Key Topics
- Installation Scenarios: Highlights different ways PV modules are mounted above roofing, varying by inclination, distance from the roof surface, and array arrangement. Details are provided for both flat and pitched roofs, supporting structures and the potential impact on fire performance.
- Fire Test Methods: Summarizes current European and international fire safety standards relevant to roofing and PV modules, including EN 13501-5, CEN/TS 1187, IEC 61730 series, and national adaptations. Discusses the lack of harmonized test methods for the combined roof and PV system scenario and highlights national initiatives developing large-scale fire performance tests.
- National Legislation: Reviews national codes and building regulations concerning the installation, spacing, and permissible configurations for PV arrays on roofs, such as required distances from firewalls and penetrations, and material requirements for both roofs and modules.
- Roles and Responsibilities: Outlines the involvement of manufacturers, installers, regulatory authorities, and insurance providers in ensuring fire safety throughout the design, installation, and ongoing maintenance of above-roof PV systems.
- Ongoing Research and Proposals: Provides an overview of European research, test protocols, and insurer requirements that influence best practices in fire prevention and risk minimization for PV systems on roofs.
Applications
This technical report is highly relevant for:
- PV System Designers and Installers: Ensures installation methods comply with regional fire safety regulations and incorporate best practices that reduce fire risks associated with above-roof PV modules.
- Building Owners and Operators: Assists in decision-making on safe PV system integration, ongoing maintenance, and compliance with national building codes, ensuring protection of property and occupants.
- Regulatory Authorities and Inspectors: Serves as a technical reference for reviewing, approving, and inspecting PV installations on roofs, supporting a harmonized approach to fire classification across Europe.
- Insurance Companies: Provides technical insights to inform risk assessment and underwriting criteria for buildings equipped with above-roof PV modules.
- Fire Safety Engineers: Facilitates the development of fire management strategies and the evaluation of real-world scenarios where PV modules and roofing systems interact during fire events.
Related Standards
Several international and European standards are closely linked to the classification and testing of fire performance for roof-PV systems, including:
- 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 external fire exposure to roofs, covering various ignition and exposure scenarios.
- IEC 61730 Series: Safety qualification for photovoltaic modules, including requirements for fire tests.
- CLC/TR 50670:2016: External fire exposure to roofs in combination with PV arrays – Test method proposals.
- IEC 63027:2023 and IEC 62109 series: Electrical safety standards for photovoltaic power systems and converters.
- CEI/TS 82-89:2023: Italian specification for fire behavior testing of PV modules installed on building roofs.
Adherence to these standards, combined with the guidance in CEN/TR 18326:2026, will support safer, more resilient integration of solar technologies into building environments across Europe.