Elioth’s was brought on board by 2Portzamparc to provide full Façade design engineering services and construction supervision for the Sisters Towers at La Défense. The building is composed of two towers connected by a bridge building. The project covers 52 (Tower 1) and 32 (Tower 2) levels from the ground floor, 220 metres high. The levels of Tower T1 are intended to be occupied mainly by offices. The levels of the T2 tower are intended to be occupied by hotel residences.

Studies cover facades with complex geometries, cold bent glass research, a CFD analysis of the natural ventilation system, the study and quantification of the integration of building skin photovoltaic panels and the study of the maintenance system.



  • City : Puteaux – La Défense (75)
  • Client : Unibail-Rodamco
  • Surface area : 220m de hauteur – 98 000 m²
  • Budget : 310 M€
  • Team : 2Portzamparc / Elioth / Setec TPI
  • Services : Conception des façades ESQ > DCE + Suivi des travaux


48.894577, 2.238228