S3DA Design was engaged to provide full structural and MEP engineering for a new three-story single-family residence located on a steep hillside lot in Oakland, CA. The project’s sloped terrain and seismic considerations required a highly engineered structural solution to safely support the building while optimizing constructability and cost.
Structural Engineering for a Sloped Site: The hillside condition was a defining factor of the structural design. Our team performed a detailed gravity and seismic analysis to address significant elevation changes, unbalanced soil pressures, and lateral forces common to sloped sites in high-seismic regions. The structural system was carefully engineered to manage vertical and lateral load paths from roof to foundation, ensuring long-term stability and performance.
The final design utilized a concrete structural frame with special reinforced concrete shear walls and moment-resisting frames, providing the necessary stiffness and ductility for seismic resilience. Elevated floor systems were designed using a combination of concrete slabs and wood joist framing, allowing efficient load transfer while accommodating architectural layouts and hillside geometry. A robust foundation system was developed to interface with the sloped ground conditions and resist overturning, sliding, and differential movement.
Deliverables included a comprehensive structural calculation package, fully coordinated construction drawings, detailed schedules and sections, and a 3D IFC model to support visualization, clash detection, and interdisciplinary coordination.
Integrated MEP and Energy Design: In parallel, our MEP team delivered a fully coordinated set of building systems tailored to the residence. The scope included HVAC design with detailed load calculations and duct layouts, complete electrical power and lighting design with single-line diagrams, and a comprehensive plumbing system covering domestic water, sanitary drainage, natural gas distribution, and roof rainwater management.
To meet California energy requirements, we prepared a Title 24 energy compliance report, providing the owner with multiple equipment and envelope options to achieve code compliance while maintaining energy efficiency and occupant comfort.
This project demonstrates S3DA Design’s expertise in delivering structurally sound, hillside-responsive solutions for complex residential projects. By integrating structural, MEP, and energy design under one coordinated approach, we delivered a permit-ready design package that balances safety, performance, and architectural intent on a challenging sloped site.
