This building housed the living quarters and dormitories of the Templar knights. It features two floors and a basement, where the entrance to another of the castle's secret passageways is located. The Templars who lived here followed a unique internal organization characteristic of the Order. At the head was the Master, responsible for the Commandery of Monzón
the administrative districts into which the Order's territories were divided. There was also a sub-master to assist him, and a lieutenant who took his place during his absences. Within the community, there were distinct ranks.
the knights and the sergeants, who were dedicated to military service; the squires, who assisted them in their duties; and the chaplains, who took care of spiritual life. The daily domestic tasks of the monastery were carried out by brothers of a lower rank.