Over the centuries, the walls of the building had been subjected to numerous layers of paint, plaster and wallpaper many of which were applied without regard for the original aesthetic.

Through extensive analysis and sampling, various layers of plaster were studied, revealing both original and later interventions. The earliest lime-based plaster layers were preserved wherever possible. In areas where the original plaster had been replaced or severely damaged, these layers were carefully removed to expose the decorative finishes beneath. Many of the wall decorations on the upper portions of the walls survived thanks to the false ceilings installed at a later stage. These ceilings protected the delicate decorations, preserving them intact despite the various changes made over time.