Solar Racking is Changing — How Will You Adapt?


By Barry Cinnamon

There is probably no more expensive and inconvenient place to work than a steeply sloped residential rooftop. As a result, mounting system parts and installation represents the second-largest cost component for an average residential rooftop installation at roughly $0.54/W of $4.93/W. Finding ways to reduce module installation costs represents a substantial cost reduction opportunity for the solar industry.

Instead of getting easier and cheaper, parts and labor costs for rooftop mounting systems are likely to get more expensive. Starting on January 1, 2015, UL 1703 Fire Testing Requirements go into effect, requiring solar modules and mounting systems to be tested together for rooftop fire resistance. UL 2703 Mounting System Requirements are also going into effect in 2015, requiring mounting systems and modules to be tested together for grounding effectiveness and mechanical strength.

The traditional solution has been the “rails & mount” system, which requires a lot of aluminum, a high parts count, and on-site rail splicing. All these factors have led to high installation labor and materials costs. To reduce these costs, two new systems have emerged: integrated racking where the racks are built into the module’s frames, and direct attachment racking where the modules are installed directly into the roofs with specialized mounts without any rails. While neither system is perfect, they both present significant improvements over traditional racking solutions by reducing part counts and labor time.


The main drawbacks for direct attachment racking and integrated racking is that they are not currently available for all applications. Integrated racking requires module manufacturers to use special frames, limiting the number of companies that offer the solution. Meanwhile, direct attachment racking is only suitable for composition shingle rooftops. Also, as a new solution, direct attachment racking technologies are still working out some kinks, particularly around roof leakage due to the higher screw requirements.

While both systems offer lower installation and material costs than traditional racking, integrated racking systems tend to offer the best overall cost savings as their usability across roof types allows for lower operational costs for installers. Market adoption of integrated racking systems will grow as more module manufacturers realize that they can capture additional downstream mounting system margins by adopting the solution. However, as the SolarCity acquisition of Zep showed, the growth of integrated racking systems will be bumpy as some module manufacturers may pursue proprietary solutions rather than adopting market standards.

As companies innovate, the cost for homeowners to go solar has dropped. However, this trend may not last due to external forces such as the expiration of the ITC, the module trade case, and the upcoming strict UL racking test requirements. For the solar industry to weather this storm and continue to grow, we must take control of our costs and implement advanced, efficient, solutions across the value chain. Modules and inverters have already made large strides in reducing costs to installers. Now it’s racking’s turn.

Barry Cinnamon_HeadshotBarry Cinnamon is the CEO of Spice Solar and Founder of Westinghouse Solar. Barry is a widely recognized expert on solar power, and a long-time advocate of its use. He holds a BS degree in Mechanical Engineering from MIT and an MBA degree in Marketing from Wharton. His work on reducing costs of rooftop solar power systems has led to over 30 issued and applied for patents held by Westinghouse Solar. He is a NABCEP Certified Solar Installer, a licensed California C-46 Solar Contractor, an active member of the Silicon Valley Leadership Group, a former President of the California Solar Energy Industry Association, Vice Chair of the Solar Energy Industries Association PV Division, and a Senior Fellow of ALF – American Leadership Forum, Silicon Valley.

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