Gladeville Baptist Church in Gladeville, TN, was experiencing costly lightning-strike damage, especially to the Direct Digital Control (DDC) system for the 90,000-SF building’s 49 HVAC units. Puckett Engineering performed a lightning study and designed preventative solutions for the church, which consisted of three adjoining structures built between 1956 and 2008. The main source of the problem was found to be the electrical isolation of the three structures. This resulted in ground differentials, especially during lightning activity, which equalized through the DDC data cables connecting the buildings. Puckett Engineering’s primary solutions included bonding the grounding systems together, improving the earth grounding, providing isolation in the data and communication circuits between the buildings, and adding surge protection. PDF Case Study.