300 I ST NE

300 I Street NE & 901 3rd Street NE | Washington, DC
Office-to-Residential Adaptive Reuse & Vertical Addition — Structural Engineer of Record: BEL Engineering
BEL Engineering served as the Structural Engineer of Record for the adaptive reuse and vertical expansion of a historic 1926 office building located at 300 I Street NE and 901 3rd Street NE, situated within blocks of Union Station in Washington, DC.
The project involved the structural conversion of the existing masonry warehouse-style office building into modern residential occupancy, with the addition of three new stories and a penthouse level above the existing structure — a technically demanding scope requiring comprehensive structural assessment of the original building's capacity to support the new vertical loads imposed by the addition.
The development totals just over 89,000 gross square feet and is being delivered in two phases, yielding 86 rental units across studio, one-, two-, and three-bedroom configurations. The structural design accommodates amenity terraces and private patios distributed across multiple roof levels, including areas with sweeping sightlines toward the U.S. Capitol.
Key structural engineering challenges included evaluating and reinforcing the existing 1926 structure to carry the imposed gravity and lateral loads of the new upper floors, coordinating the transition between the existing masonry system and the new lightweight addition, and detailing the podium third-floor condition for horizontal separation.
This project reflects BEL Engineering's expertise in adaptive reuse structural design — balancing the constraints of historic construction with the demands of contemporary residential programming and multi-story vertical addition.