During the course of the work, it was observed that the Minoan masonry in most parts of the Palace was set, without foundations, on the marly limestone (kouskouras) or on Neolithic layers. The rescue work on the masonry conservation-restoration consisted mainly of consolidation of the masonry, floors, mortar and plaster. The materials themselves (poros stone, limestone, gypsum) presented problems, which were treated as part of the stone conservation project.
At the same time, areas were configured or filled in where necessary, retaining walls or low walls were built in order to level the ground and permit the comfortable circulation of visitors, and other areas were roped off to protect them as much as possible.
The masonry conservation-restoration work at the Palace of Knossos consisted of the following stages: first the cement mortar used in earlier interventions was removed, in order to conserve the mud-brick and stone Minoan walls; this mortar was, of course, incompatible with the ancient building materials. The joints were then cleaned, consolidated and filled with new, compatible material known as “Theran mortar”, whose ingredients include Theran soil, quarry sand and slaked lime.