The cover of large diameter tanks (DN > 6m) is very useful in case of dangerous and corrosive fluid storage. In fact, the roofs that we offer allow a protection of people and a containment of harmful gases. Furthermore, the use of operating constraints such as agitators, hatches, flanges does not hinder the use of this type of roofing in any manner despite its light weight and, on the other hand, benefits from its mechanical resistance.