PV array dead load is typically expressed in kN/m² or kg/m². Modern crystalline silicon modules weigh approximately 10 to 13 kg per panel, and the mounting system adds a further 2 to 5 kg/m² depending on configuration. Combined, a typical rooftop array adds 15 to 20 kg/m² of permanent dead load to the roof structure.
For ballasted systems on flat roofs, total dead load including ballast can reach 40 to 60 kg/m² in perimeter zones. Structural engineers convert these values to kN/m² for use in Eurocode load combinations. The PV dead load is applied as a uniformly distributed load over the array footprint for assessment of purlin bending, shear, and deflection under Eurocode 3.