The new Marriott International Headquarters in Bethesda, Maryland, is the home for Marriott’s corporate associates and a global hub for their research and development operations. The owner desired a focal point for their lobby space – but one that had a thin profile while also providing interactive stadium seating. 

IMEG provided structural engineering design for the featured stair in the building’s lobby, which appears as though it is floating with very little structural support. A first-floor mezzanine cantilevers out over the lobby space, acting as the mid-landing of the stair, with concrete beams anchored into the column grid to create a 90-foot “floating” stair effect without additional posts.

Challenges such as the thin profile, cantilevered glass guardrails supported by structural treads in lieu of stringers, and concealed fire sprinklers required close collaboration among the entire design team and manufacturers. This partnership between the structural engineers, architects, and the terrazzo manufacturer’s engineer ensured that minimal steel was used to create the floating staircase and maintain the architect’s aesthetic. 

IMEG also provided design for the following: 

• Heavily loaded areas
• Skyfold wall
• Telescoping partitions
• Partial height walls
• Floating millwork
• Miscellaneous steel structure for the servery
• Support of the feature chandelier/fixture in lobby
• Support of the video wall in the lobby