121 Seaport is a 17-story office structure with an elliptical form that results in 15% of energy savings due to less solar exposure, while also avoiding the adjacent underground MBTA Silver Line. There are 400,000 SF of office space above a two-story, 50,000 SF retail podium. 121 Seaport utilized an up-down construction method and condensed the timeframe by six months. The foundation elements were installed three-stories below-grade, followed by the ground-level slab. The superstructure was erected simultaneously as the 270-space below-grade parking garage was being excavated. During construction the remains of a shipwreck were found, now represented by a statue. McSal completed the fit-out for PTC’s 250,000 SF global headquarters.