Cementitious screed with semi-wet consistency, normal setting, fast drying, controlled hydraulic shrinkage, fiber-reinforced with stainless metal fibers and specific additives to achieve high thermal conductivity. It allows the preparation of screeds for high-energy efficiency radiant floor air conditioning systems, perfectly flat, absolutely stable, without cracking and with reduced moisture content, reducing the time for thermal testing and the laying of subsequent coverings. Product for professional use.