Case Engineering has completed the structural design for a new Anytime Fitness location in San Diego, California, transforming a former Chase Bank into a modern 24-hour fitness facility. Working in collaboration with Trileaf Corporation, a St. Louis-based architectural firm, Case Engineering developed a creative mezzanine support system that adds 2,400 square feet of new workout space within the existing building footprint.

Located at 365 W Washington St. in Mission Hills Plaza, the 4,000-square-foot structure was adapted into a welcoming, full-service gym while preserving its original foundation and envelope. Anytime Fitness, a global franchise of 24-hour, co-ed gyms, emphasizes community, convenience, and personalized support for members who enjoy 24/7 access, digital workouts, and individualized coaching.

The building’s original design included deep foundations, concrete masonry unit (CMU) bearing walls, and a wood-framed roof system. Trileaf’s architectural concept added a mezzanine along the interior perimeter to expand usable space without altering the building’s footprint.

As the project’s structural engineer, Case Engineering faced the challenge of supporting the new 2,400-square-foot mezzanine while meeting stringent clearance and load requirements. The team implemented a low-profile composite steel beam framing system to maintain headroom both above and below the mezzanine and accommodate the building’s existing roof height.

“The existing structure is supported by concrete grade beams and deep foundation-drilled piers,” said Ardie Mansouri, P.E., Senior Structural Engineer and Principal at Case Engineering. “Our design required placing new mezzanine support columns directly over existing grade beams, which we reinforced to handle the increased loads. The mezzanine’s additional mass also elevated seismic demands, so we introduced new shear walls supported by deep foundation elements to meet seismic safety standards.”

The new mezzanine now houses cardio and training equipment including treadmills, ellipticals, and private training areas. It is accessible via a staircase and ADA-compliant lift to ensure inclusive access for all gym members.

RPS GC, Inc., based in Costa Mesa, Calif., served as the general contractor on the adaptive reuse project. The grand opening for the new Anytime Fitness was celebrated on January 25, 2025.