The former Philadelphia Stock Exchange Building contained over 190,000 square feet of space in a 12-story, concrete office building.  The challenge was to convert and expand the building to accommodate a 320-room luxury hotel.  The solution included a horizontal twelve story steel frame expansion of 90,000 square feet, a cantilevered porte-cochere added to the front of the building and the addition of two levels of below-grade parking.  The Sofitel Philadelphia facilities include an elegant lobby, a business center, a fitness center and a high end dining venue.