Solar Requirements Are Moving from Policy to Practice

Europe is entering a major phase of rooftop solar deployment. Under the recast EU Energy Performance of Buildings Directive (EU) 2024/1275, Member States must progressively ensure the deployment of suitable solar installations where they are technically suitable and economically and functionally feasible. The timetable begins with new public and non-residential buildings larger than 250 m² by the end of 2026 and expands to additional public, non-residential and residential building categories in subsequent years.

The UK is moving in the same direction. The government has stated that rooftop solar will be included on almost all new homes under its new building standards. Together, these measures are expected to increase the number of photovoltaic systems installed directly on, or integrated into, building roofs.

Why Rooftop PV Fire Performance Matters

A photovoltaic module installed on a roof becomes part of a larger fire-safety system. Its performance can be influenced by the roof covering, mounting arrangement, inclination, airflow and the space between the module and the roof surface. Under external fire exposure, these factors may affect how flames travel across the roof and how heat is transferred to the underlying construction.

For this reason, rooftop fire testing needs to examine more than whether an individual material can be ignited by a small flame. Typical assessment points include:

l flame spread across the surface of the roof or PV assembly;

l fire penetration and exposure of the roof deck;

l burning or glowing components that detach from the test assembly;

l the effect of intermittent flame, burning brands and wind-driven fire; and

l continued burning after the specified exposure period.

Supporting PV Module and Roof Fire Evaluation

The TESTECH FTech-UL790 Roof & PV Module Fire Test System is designed to simulate controlled rooftop fire exposure and evaluate the fire performance of roof coverings and photovoltaic module assemblies. The system provides regulated airflow, burner heat output, temperature monitoring and computer-based data acquisition for repeatable laboratory testing.

The system supports testing based on:

Depending on the applicable method, the equipment can reproduce Class A, B and C exposure conditions and support flame-spread, intermittent-flame, burning-brand and flying-brand evaluations. It is intended for PV manufacturers, roofing-material producers, third-party testing organizations, certification bodies and research laboratories.

Different Markets Require the Correct Test Route

Fire-test requirements are market-specific. UL 790 and ASTM E108 are widely associated with North American roof-covering classifications. European and UK projects may instead reference CEN/TS 1187 test methods and classification according to EN 13501-5 or BS EN 13501-5. The test configuration and classification route should therefore be confirmed against the destination market, local building regulations and the intended installation before equipment selection or testing begins.

The expansion of building-mounted solar is creating opportunities across the PV supply chain, but it also increases the need for credible fire-performance data. Appropriate laboratory testing can help manufacturers improve product design, support certification work and provide building professionals with greater confidence in rooftop PV installations.

About the FTech-UL790

The FTech-UL790 combines a large roof test deck, adjustable test angle, controlled airflow, high-capacity gas burner, temperature monitoring and modular data acquisition. The complete installation is approximately 6,000 × 2,200 × 2,000 mm and is engineered for dedicated fire-testing laboratories.