Solar Industry Avoids Much Stricter Requirements in Code Change

By Christian Roselund

The body that sets buildings codes for the United States and some nations in Latin America, the Middle East, and other regions has increased the structural requirements for solar installations but has made no move to clarify the structural requirements of wind turbines. On 1 November 2022, the International Code Council Online Governmental Consensus Vote concluded, providing preliminary approval for a modified proposal calling for most ground-mounted solar installations to be assigned to Risk Category 2 (RC II). This is the same category as most residential and commercial buildings. The body did not approve requests to clarify that wind turbines should be RC II, leaving wind turbines in a gray area.

For solar, this will mean more stringent requirements than the RC I assignment that the solar industry was advocating for. However, these are not nearly as demanding as the RC IV that advisors to the Federal Energy Management Agency (FEMA) had called for in a proposal earlier this year (see the 18 October 2022 U.S. Energy Transition Report for more details). CEA’s Engineering Services team confirmed that a change to RC IV would have substantially increased the structural requirements and cost of building solar installations.

For rooftop solar installations, the risk category will be the same at that of the building on which the solar is installed. The only solar installations that will be held to RC IV are those that are on RC IV-assigned buildings, which includes hospitals, fire stations, and other buildings housing emergency services, or carport solar installations that emergency vehicles are parked under.

The Council also provided preliminary approval of a change that specifies that RC III structural requirements will apply to power generating facilities with individual units 75 megawatts-ac and higher. As it also clarifies that an individual unit can be an individual wind turbine, this should exempt wind farms from this requirement. However, the Council did not move on a proposal to classify wind turbines as RC II, which advocates say aligns with best practices and previously published
industry guidance.

These votes represent preliminary results and are subject to certification by the validation committee and confirmation by the International Code Council Board. If certified, these changes will take effect with the 2024 Building Code, which upon publication will form the basis for local building codes in the United States and internationally.

Source: Preliminary 2022 Group B Online Governmental Consensus Vote (OGCV) Results (International Code Council.