The evolution of solar roofing regulations

By Emma Peterson. 

Learn why UL 2703 is so important and what the next steps for solar standards are.  

In an ever-changing industry, codes and standards are always developing and adapting. A great example of this is the UL 2703, which was developed as a way to evaluate solar racking components. In this episode of Roofing Road Trips®, Heidi J. Ellsworth spoke to Mark Gies and Dustin Haddock of S-5! to talk about how codes and standards like UL 2703 come to be and how contractors should adapt in preparation.  

The development of UL 2703 came from a gap in the certifications and regulations, where there were no guidelines for solar racking systems. Today, if you want to get a solar rack project approved, you have to be certified or demonstrate you are compliant with UL 2703.  Dustin shared a bit about what this covers, saying, “A big part of 2703 is fire. So if you have a Class A roof, but you put a bunch of solar panels on there, which are highly flammable, is it going to change the rating of the roof? And then the other one is mechanical load. Is the racking component fixing the module in such a way that the module's not going to get overloaded with snow or overloaded with wind or somehow slip out?” 

But this standard still has its limitations and subsequent gaps. One such gap is roof attachments. Mark elaborated, “UL 2703 deals with the racking, but not if you screw it down or use weight to hold it down or some other type of attachment. That's out of the scope.” This gap makes it confusing when it comes time to install, as Mark explained, “There are other tests, but everybody has their own version and it's very confusing and chaotic on exactly where the interface is of the solar mounting system and that roof, that interface has been this gap that I think has created a lot of uncertainty and just creates more inefficiency in the permitting process.” 

In response, UL 2703A is in the process of getting developed. Mark explained a bit of what this would cover, saying, “UL 2703A looks at waterproofing and then it looks at material. This is about flashing now. So it's about as installed, how waterproof it is, and then it also looks at the material to make sure that it's durable, that it will withstand the test of time.” This is not a standard yet, rather it is just a subject that they are working hard to develop to the point where it can become a standard. For reference, Mark and Dustin were working on UL 2703 for five years before it became a standard.  

Read the full transcript or Listen to the whole episode for more about UL 2703 and the UL 2703A.