Solar Mounting Changes: What They Mean for Your Project

Britain’s solar energy sector has been hit with a significant regulatory shake-up, effective from May 10, 2025, following a major update by the Microgeneration Certification Scheme (MCS) to its 012 standard for solar mounting systems. This change has resulted in numerous flat roof mounting products being abruptly removed from the certified list, causing concern throughout the industry and highlighting a critical new era for solar installation compliance, writes Phil Wiltshire, operations director for Pensdown, the electrical people.

While we, as a company and our customers, have not been directly impacted by the withdrawal of specific products, the broader implications of these stricter certification requirements affect every facet of the solar supply chain, from manufacturers to installers and ultimately, the end consumer.

This updated standard represents a significant evolution in how solar mounting systems are assessed and approved. The MCS has expanded its scope to include both mechanically and non-mechanically attached mounting systems designed for flat roofs. Prior to this update, pitched roof mounting systems were already subject to rigorous certification, but flat roof installations often operated under a different set of guidelines, largely relying on a clause, known as 5.5.5. within the MCS 3002 (The Solar PV Installation Standard) that permitted the use of uncertified custom systems, provided they met specific Building Regulations requirements and were backed by written confirmation from designers and suppliers.

MCS 012 v3.0 now explicitly covers flat roof mounting systems, that previous relied on that clause for uncertified systems. This means that, moving forward, flat roof mounting systems are now mandated to hold explicit MCS 012 certification, just like their pitched roof counterparts. This shift is a testament to the industry's commitment to raising standards, ensuring greater consistency and ultimately enhancing the safety and reliability of solar installations across the board.

The immediate consequence of this regulatory tightening was the withdrawal of certifications from the MCS database for several solar mounting kit products. This created understandable concern among installers who had either recently completed projects using these now-uncertified products or held substantial stock.

Potential for disruption

Recognising the potential for widespread disruption, MCS quickly responded by announcing a crucial six-month grace period. This grace period functions on two levels. Firstly, there's a general time period for uncertified flat roof systems until August 10, 2025. This allows a temporary window for installers to continue registering flat roof installations using uncertified mounting systems, provided all original requirements of Clause 5.5.5 are meticulously met. This interim measure is designed to give manufacturers of these systems adequate time to navigate the new certification process and bring their products into full compliance.

Secondly, and perhaps more directly impactful for those affected, a specific grace period was extended for those products whose individual certifications were withdrawn on May 10, 2025. For installations utilising these particular products, they are deemed compliant if their MCS certificate is issued on or before November 10, 2025. After this critical November date, these specific products will no longer appear in the MCS database as eligible for new certificates.

It's important to clarify that this change does not automatically imply that the withdrawn products are inherently unsafe or poorly designed. Rather, it signifies a shift in the regulatory landscape, demanding a higher, more standardised level of certification for these specific types of systems, especially those destined for flat roofs.

The manufacturers whose products were impacted, such as Alumero, Clenergy, K2 Mounting Systems, Mounting Systems GmbH, Solar Slate Plate, Wagner and Fastensol, are actively working to re-certify their products under the new, more stringent guidelines. For now, their systems are being temporarily re-listed in the MCS Product Directory with a clear "(GRACE PERIOD)" designation and a defined certification validity window from '10/05/2025 to 10/11/2025'.

So, why has this change occurred? At its core, the update to MCS 012 is a proactive measure to enhance the overall safety, long-term reliability and consistent performance of solar installations throughout the UK. Previously, the custom design route for flat roofs, while offering flexibility, inherently meant less consistent scrutiny compared to the well-established certification processes for pitched roof systems.

This new standard aims to close that gap, ensuring that all mounting systems, regardless of roof type, meet a robust, standardised level of quality, testing and compliance. It’s about building greater confidence in solar technology as a national infrastructure asset.

For a company like Pensdown, which specialises in the intricate electrical work that underpins these solar installations, these regulatory changes underscore our foundational commitment to quality and foresight. We understand that the long-term success of a solar project hinges not just on the efficiency of the panels, but on the integrity of every component, from the electrical cabling and inverters to the very system that secures it to the roof.

Meeting the highest standards

Our selection of mounting solutions has always been based on adherence to the highest existing standards and a careful evaluation of their engineering robustness, ensuring that our installations are built to endure the diverse environmental conditions of the UK. The fact that Pensdown has not used any of the mounting systems specifically listed as withdrawn reflects our established due diligence and our focus on partnering with manufacturers whose products consistently meet or exceed the most stringent industry benchmarks, even before new regulations come into play.

For installers, the message is now clear - staying informed about the latest MCS standards and diligently cross-referencing the MCS product directory is no longer optional, but absolutely critical. They must ensure that every mounting system used, whether for a new build or a retrofit, is either fully certified under the new MCS 012 v3.0 or falls strictly within the defined grace periods and meets all associated compliance requirements.

Without a valid MCS certificate, homeowners and businesses may find themselves ineligible for crucial government incentives. This places a significant burden of responsibility on installers to update their procurement processes, retrain their teams and meticulously manage their project timelines to align with these new deadlines.

For consumers, whether you're a homeowner considering solar panels or a business planning a large-scale commercial array, these changes highlight the importance of choosing a reputable and knowledgeable installer. If you've had a solar PV system installed recently, particularly around May 2025, it’s a prudent step to confirm with your installer that the mounting system used is fully compliant with the updated MCS standards and that your MCS certificate was issued within any relevant grace periods.

For those planning new installations, engaging with an MCS-certified installer who can clearly demonstrate their use of fully certified mounting systems (and all other components) is paramount to safeguarding your investment and ensuring eligibility for available incentives. It’s a moment to ask probing questions, ensuring transparency and adherence to the highest industry benchmarks.

In essence, the UK solar industry is currently navigating a major transition in how solar roof mounting systems, particularly for flat roofs, are regulated and certified. While this process might present temporary challenges for some, its overarching goal is to raise industry standards, enhance long-term safety and guarantee the reliable performance of solar installations across the nation.

For Pensdown, this evolution serves as a powerful reinforcement of our commitment to excellence, reminding us all that building a sustainable future requires not just innovative technology, but unwavering dedication to the highest standards of quality and compliance in every single component, from the panel to the mounting and from the inverter to the final electrical connection.