Structural design for Casita in Chandler, AZ
S3DA Design is providing structural engineering for a casita addition in Chandler, Arizona, delivering a complete foundation-to-roof structural package for a new ground-level addition with an upper-level wood-framed roof structure.
S3DA’s Structural Scope
- Foundation design to support vertical and lateral loads from the new upper structure
- Structural slab-on-grade design
- Wood framing analysis and design for gravity and seismic demands
- Lateral system options evaluated for cost-effective performance, including:
- Light-frame wood shear walls
- Strong walls / steel wall panels
- Special moment frames
- Load-bearing wood framing for gravity loads
- Elevated floor design, including evaluation of:
- Wood joists / TJI / beam-joist systems
- Pre-engineered floor truss requirements
- Main structural elements, including glulam and/or steel beams, as required to support intermediate framing
- Coordination with the architectural team using an IFC model for accurate 3D structural representation (true size and location)
- Structural calculation report suitable for project documentation and review
Key Challenges & Solutions
Casita additions often require balancing structural performance with architectural constraints and budget. Our team evaluated multiple lateral system strategies—ranging from wood shear walls to steel wall panels and moment frames—to identify the most cost-effective solution while maintaining a clear load path for gravity and seismic forces.
The Result
S3DA delivers coordinated, constructible structural design—supported by clear calculations and a precise 3D structural layout—helping streamline design coordination and support a smooth path to permitting and construction.
