Refurbishing with steel- Building on, building along and building upgrade

The topics covered in this second part of the article on steel rehabilitation concern global interventions on a building scale. . This work includes building extensions, both horizontal and vertical, as well as large-scale construction inside existing buildings or behind façades that have been preserved for historical reasons. The covering of residual areas such as patios or courtyards is also a chapter in its own right.

All these issues are particularly important in today's context of urban densification, which now prevails in all urban analyses for obvious reasons of sustainable development, but also to compensate for the scarcity of building plots. This redefinition of structural forms is often accompanied by changes of use and changes in building class due to typological changes and/or changes in regulatory category for fire, earthquake, climatic and/or operating loads. It is also an opportunity to adapt to new standards or to repair existing structures, such as the corrosion pathologies that appear when existing structures are exposed.

The redefinition and/or repair of building envelopes is often a consequence of these major modifications to existing buildings, just as it is today an integral part of urban renewal. Façade repair solutions, to achieve insulated constructions in line with new thermal regulations but meeting the aesthetic criteria dictated by architects, are now unavoidable. Steel offers a wide variety of solutions that can be applied to all types of structure (masonry, iron and cast iron, reinforced concrete and timber frame). Its advantages range from its strength to the wide range of possible modenations and colors. .