PV System Design for a rooftop PV System where the Panels are attached to a structural concrete roof, with less than 50 Panels. Need Cure Strength of Concrete, and Thickness of Slab to Complete Design. If this information is not known, we can schedule a property survey where the pullout strength in Concrete can be physically measured for an additional fee. Inverter System may be either Enphase, SolarEdge, or Tesla, with No Battery Storage.