Reuse of used structures
Structural repairs of structures with steel Adaptation to new loads, thermal and acoustic standards

The superimposition of more recent constructions on existing structures is very often visible in older buildings. It's also not uncommon to find structures whose foundations date back to Greek times, covered by a Roman layer, which itself bears Gothic or Renaissance strata. This way of reusing already-built structures shows that past generations were more aware of the economy of materials and favored their reuse.

The Château de Périgueux in figure 77 is typical of these superimpositions.