The Sala della Volta Rossa (room 33), overlooking the Great Peristyle and covered by a barrel vault with a southern apse, features a remarkable decorative scheme. Its striking cinnabar-red background gives the room its name, complemented by precious pigments such as Egyptian blue and gold leaf highlights. Originally, the walls were lined with polychrome marble panels up to about 4.40 m, of which only a small trace remains at the corner between the north and east walls. Above these, the painted decoration unfolds with architectural perspectives, suspended figures, Dionysian scenes, and rich stucco details.

• State of conservation

  When restoration began, the surfaces faced complex conservation challenges due to centuries of humidity, condensation, temperature fluctuations, and rainwater percolation. These had caused:

  • Extensive biological growth (algae, mosses, and higher plants), especially in the apse, with roots penetrating the paint layers;
  • Calcareous deposits of varying thickness, sometimes layered with remnants of ancient backfill;
  • Salt efflorescences, leading to small losses of the painted surface and exposing the plaster beneath;
  • Irreversible color changes of the cinnabar to black or brown;
  • Oxidation of metallic elements.

• Restoration work

  Restoration focused on stabilizing the surfaces, cleaning, and aesthetic recovery of the walls. The interventions included careful removal of biological growth and deposits, consolidation of plaster, stucco, and paint layers, reattachment of detached areas, and sensitive reintegration of missing decoration, respecting the archaeological character of the room.

  Thanks to this work, the hall’s extraordinary richness of materials and decorative design is now fully legible, balancing aesthetic presentation with preservation of its fragile original finishes.

  

  Opus sectile parietale, traccia presente all’angolo tra prospetto est e nord

  

  Prospetto nord, prima e dopo il restauro

  

  Tassello di pulitura in volta