new rules for roof integrated solar

MCS012 Comes into Force

New Standard has Significant Implications for Roof Integrated Solar

November 2015


After several delays over the last few years, the MCS012 pitched roofing test requirements will become mandatory for solar installations from 2nd May 2016. This may have some significant implications when comparing different roof integrated PV systems. The testing doesn?t necessarily indicate a pass or failure. Instead, installers must use declared performance values from the tests to confirm viability for the predicted wind forces and compliance with the Building Regulations for fire.

Following fire-resistance failure of some PV modules in testing, MCS012 mandates that roof integrated systems that work with interchangeable modules will comply with MCS and Building Regulations only when used with the family of modules that were actually tested, and the fire rating cannot be extended to other modules. In practice, this means that systems claiming to work with any module are likely to require installation of fire board or a fire-proof membrane behind the solar installation to achieve compliance. Clearline systems from Viridian Solar have AA fire rating across the full range, so are unaffected by this change.

Wind loads vary significantly across the UK, so installers will be required to verify that the system has a wind resistance higher than the forces to be encountered for every installation. The graph below shows the tested performance of Clearline Fusion from Viridian Solar, plus a couple of other roof-integrated products, relative to potential UK wind load scenarios. While other systems may struggle to provide sufficient strength for some locations, you can proceed with confidence when selecting Clearline Fusion.


See Also

performance of solar panels installed in the roof

009 - MCS012 - Pitch Perfect


What the introduction of MCS012 means for solar installers. How the new requirements for wind uplift resistance, fire ratings and weathertightness impact roof integrated solar systems.