One of six buildings excavated at Lion Walk laid out in a fashion characteristic of Roman legionary barracks. The material used to construct the superstructure of the principal walls was sandy daub laid in the form of sub-dried blocks. These were placed over timber ground-plates which rested along the tops of the mortared plinths. The plinths of this building had been robbed and the pre-Boudican floor levels were not examined.

Between AD 49-60/1 substantial alterations took place within the building. New floors were laid which were made from the debris left after the demolition of the internal walls. This was particularly clear in one section where the floor of the later building could be seen to contain large lumps of daub wall and fragments of wall plaster. The latter implies that the military buildings were plastered at least in part or that the plaster was secondary, perhaps added in the civilian phase. Three new partitions were laid out east-west. These incorporated timber ground-plates which survived as charcoal in the bottoms of the slots.<1>