During several excavation campaigns in 2008 and 2009, a major archaeological site was uncovered under part of the Place de la République in Luxeuil-les-Bains, in the historic heart of the old town. Around the remains of the old parish church of Saint-Martin, archaeologists were able to uncover the remnants of a 2nd century Roman villa and religious buildings dating from the Roman Empire to the end of the Middle Ages.
Considering the importance of this site, the city decided to preserve the remains and to showcase them by building a structure over them, to become a central part of discovering the city.
The architectural and technical urban choices
The project involves both the development of the Tourist Office in an existing building and the construction of a structure over the Saint-Martin archaeological site.
The old building, housing the Tourist Office, has been subject to a major interior rehabilitation, without major modification of its volume. All the wooden floors were taken up and replaced. The roof framework were preserved and reinforced.
Adjacent to the Tourist Office and installed on the old Place de la République, the &cclésia, envelopes the remains while redesigning the urban spaces that surround it: the esplanade on the shopping street, a small esplanade at the back opening onto a view of the old town houses in the Gothic or Renaissance style.
Inside, the volume of the structure forms a unitary whole entirely dedicated and constrained by the remains. Following the strict perimeter of the excavations, the roof of the structure covers the whole of the excavations in one section over a vast area of 765 m2. The construction choice of the framework was naturally made in favor of an orthonormal three-dimensional structure for its ability to carry a large length horizontally (up to 24 m). The thinness of the metal and the principle of the grid brings a graphic and abstract dimension to this new contemporary stratum which refers to the orthonormal squaring traditionally used by archaeologists to establish their surveys.
The framework is made of raw weathering steel, built on the basis of a square mesh of 2 m x 2 m oriented along the axis of the principal remains on the site, the church of Saint-Martin.
This geometry structures, governs and gives the measure to the whole composition. It’s applied to the entire building envelope, from the non-load-bearing facades with their grid of Douglas fir wooden columns, resting on low walls that form ground beams.
The loads are distributed on pilings placed between the remains that have been precisely positioned according to the profile of the land.
This project is the result of collaborative work within the project management team with the archaeologist in charge of scientific monitoring. Particular attention was also paid to the scenography, the lighting and the control of hygrometry.