Large solar panels, bigger challenges? Here’s how to stay in control of quality and yield

Large solar panels seem like the logical step towards higher yields in solar C&I projects, thanks to their higher power output in watt-peak (Wp). In commercial rooftop solar projects, however, they also introduce unique challenges. Think of weight, dimensions and the forces acting on the roof. Without proper preparation, this can quickly lead to delays, quality issues and unexpected costs. The cause is rarely the panel itself, but more often the system choice, preparation, planning or the collaboration between design and execution. 

In this blog, we share practical insights, technical tips and a checklist for successful commercial rooftop solar projects with large solar panels. 

Large solar panels on flat roofs: practical challenges 

In practice, we see that installing large solar panels differs significantly from working with smaller or standard panels. In solar C&I installations, installers encounter several clear challenges: 

• Heavy and unwieldy : Big solar panels are physically heavy and difficult to handle. Without sufficient manpower and appropriate tools, this can lead to installation errors, delays and an increased risk of injury. 

• Risk of deflection and panel damage: Incorrect positioning of panel clamps (on the short side), especially with huge panels longer than two metres, can cause deflection. This increases the risk of microcracks, reduced yield and potentially voided warranties from the panel manufacturer. 

• Complex layout due to roof obstacles : Because of the large dimensions, placing panels around roof penetrations and installations can be more challenging. Good preparation ensures a fast and efficient installation. A poorly designed layout leads to time loss during installation. 

• Increased load on the mounting system : Large solar panels catch more wind and therefore require a well-designed PV ballast system for commercial projects. If this is not calculated correctly, the structure may shift or roof damage may occur. 

In short: successful installation of large solar panels requires thorough preparation. 

Installation tips for large solar panels 

Successfully installing large solar panels requires precision, safety and a smart approach. With the right preparation and tools, installers can work more efficiently and reduce risks in solar C&I projects. 

Work with two installers and dedicated tools
Always installing big solar panels with two installers and using specially designed tools such as alignment sets ensures correct installation. This reduces the risk of errors and delays.

Use the correct clamping positions
Large PV panels should be clamped on the long sides. This distributes the load more evenly across the panel frame, reduces the risk of deflection and helps prevent microcracks.

Create a detailed layout plan in advance 
A roof scan and a clearly visualised layout plan help installers place large solar panels quickly and efficiently, avoiding on-site improvisation. Pay close attention to panel dimensions and roof obstacles.

Choose a mounting system suitable for large PV panels 
With a carefully engineered PV ballast mounting system, wind loads and other forces are safely absorbed. This prevents shifting, roof damage and long-term risks. 

Collaboration between engineering and installation 

In addition to technical preparation, collaboration between engineering and execution is crucial in commercial rooftoop solar projects. Large solar panels require thorough preparation so that everyone involved knows exactly what needs to be done.

It is also essential to support installers who will ultimately work with the flat roof solar mounting system and large panels on site. This can be done through on-site support or hands-on training sessions. Such support ensures installers become familiar with the system and can install it safely and correctly. 

Checklist for successful projects with large solar panels:

• Start with a thorough roof scan as the foundation of the entire commercial rooftop solar project.
• Create a detailed layout plan, taking pv panel dimensions and roof obstacles into account. Need help? Request free project advice for large solar panels (form).
• Select the right flat roof mounting system that matches your panel type and project requirements.
• Heavy panels or high wind loads? Choose a system that clamps on the long side, such as the ValkPro+ Max Nextgen.
• Ensure clear alignment between engineering and installation before the project starts.
• Invest in on-site training or guidance when introducing new mounting systems. 

Need advice for your project? 

Large solar panels offer many advantages for solar C&I but require extra attention on flat roofs. The key to a successful commercial rooftop solar project lies in thorough preparation, a well-considered system choice and strong collaboration between design and execution. Combining these elements helps prevent delays and minimise quality risks.

Would you like certainty about the right choices for your commercial project? We are happy to advise you on the optimal mounting system and layout for flat-roof projects of any size. Leave your details and we will support you from project start to professional, worry-free completion.