A modular system for use in construction, including a first panel, placed vertically, and a second panel, placed horizontally, each provided with a galvanized reinforcement (3) filled with a layer of insulating material. The galvanized reinforcement includes a first net, a second net and a third net transversal to the other two nets to join them. The modular system further comprises an anchoring system between the first panel and the second panel. This anchoring system includes at least one first bracket inserted in the first panel and in the second panel at the respective first nets, and at least one second bracket inserted in the first panel and in the second panel at the respective second nets.