The energy market in Mexico is facing changes due to the incorporation of clean energy certificates (CEL) on the Electric Industry Law (LIE, Ley de la Industria Electrica). One of the aims is to increase the percentage of clean energy use in the national energy matrix. Consequently, the integration of energy efficiency strategies prior to the incorporation of renewables has become essential at different levels. Industrial buildings have significant heat gains and losses through the envelope, mainly due to their vast surface and simple construction systems. This work analyses the typical envelopes of industrial buildings in Mexico and the effect of industrial rooftop photovoltaic (PV) systems over the annual energy consumption. It was found that for temperate climates, the best option would be to insulate the roof. For cities with warm climates, the best approach is to implement a cool roof on a non-insulated layer or to simply insulate the roof. Additionally, the industrial buildings with metallic roofs situated in warmer climates would benefit the most from the implementation of rooftop PV systems. After all, the results point out that the decrease in the required CELs would not influence the savings.