IMEG provided structural engineering design for all three phases of Sentinel Square, a 1.5 million-sf high-security office complex located in the NoMa District of Washington, D.C. The complex appeals to federal and local government agency tenants due to its high-security features, environmental friendliness, modern and efficient work spaces, and affordability.

Phase I included a 12-story, 440,000-sf office building above three levels, 118,000-sf of below-grade parking (317 spaces) located at 90 K Street, NE. Phase I, a LEED Gold certified cast-in-place concrete structure, is designed to meet Level IV Security Protocols in accordance with GSA’s ISC Design Criteria – including 30-foot stand-off distances, progressive collapse avoidance, hardened structure and facade, blast resistant glass, distinct garage structures, expendable entry ways, and a separate vertical transport from garage to security check-point.

Phase II is a 12-story, 304,000-sf office building above four levels of below-grade parking, 108,000-sf (220 spaces) located at 1050 First Street, NE and is LEED Silver certified. Phase III is a 12-story, 517,500-sf office building above three levels of below-grade parking, 161,500-sf (320 spaces) located at 45 L Street, NE.

Phase III is pursuing LEED Silver certification and estimated to be complete in 2020. Like Phase I, Sentinel Square Phases II and III are also designed to meet Level IV Security Protocols. A courtyard, landscaping amenities and finishes that mirror and complement one another unify the three buildings on the site.