81 Boulevard Voltaire (Hotel / Hospitality)
A major technical challenge in a highly constrained urban and heritage context.
The project involves the preservation of an existing building dating from the late 19th century, whose entire internal structure is made of timber (columns, beams and floors), while the load-bearing masonry façades are approximately 50 cm thick.
One of the project's main technical challenges is the construction of two additional basement levels, requiring excavation to a depth of approximately 10 m beneath the preserved existing building. The existing building footprint, approximately 550 m² (representing 35% of the total plot area), is maintained and supported throughout the construction works. Meanwhile, the new basement levels extend to more than 1,200 m² per level, representing nearly 80% of the building footprint, in order to accommodate the technical areas and back-of-house facilities of the future hotel.
This intervention required highly complex execution design studies, addressing issues including underpinning of the existing structure, temporary and permanent stability of the preserved façades, retention and support of the existing timber structure, as well as the interaction between the new reinforced-concrete structures and the existing heritage building.