Spiral Staircase Product Development for The Iron Shop
Client
A renowned U.S.-based manufacturer of spiral staircase kits, approached Zetacadd Engineering Services to support the development of a new spiral stair product line. The goal was to create a fabrication-ready and installer-friendly product that could be produced at scale and easily assembled by end users.
Zetacadd partnered with client through every critical stage—from design engineering to customer documentation.
Objective
- Translate product vision into a fully engineered spiral stair kit
- Create a modular and scalable design for multiple stair diameters and material variants
- Ensure code compliance and user safety
- Develop a professional-grade installation manual for residential and commercial installers
Needs
- A fully engineered spiral stair kit that is modular, scalable for various diameters and materials, compliant with safety codes, and supported by a professional, user-friendly installation manual. The product needed to balance aesthetic appeal, structural integrity, manufacturing efficiency, and maintain dimensional accuracy across different materials.
Challenges
- Designing a staircase system that balances aesthetic appeal, structural integrity, and manufacturing efficiency
- Maintaining dimensional accuracy across different materials (metal, wood, vinyl)
- Communicating complex assembly steps to a non-technical audience
- Ensuring the design meets the California Building Code (CBC 2019) and L.A. Standard #111 guidelines
Solution
- Product Engineering & Design Refinement
- Zetacadd collaborated closely with the client’s design team to engineer every component of the stair system:
- Center pole sections with modular joinery for variable heights
- Tread assemblies designed for strength, simplicity, and visual appeal
- Spindle and handrail interfaces for structural stability and ergonomic flow
- Top landing and railing details optimized for ease of assembly
- Through detailed 3D modeling and feasibility analysis, we ensured the design was cost-effective for production and simple for users to install.
- Fabrication-Ready CAD Drawings
- We produced a comprehensive technical drawing set, which included:
- Exploded views and assembly sequencing
- Precise hole locations, tolerances, and fastener specs
- Fixing techniques and part identification
- Clear fabrication standards for manufacturing partners
- The result: faster production turnaround and reduced dependency on rework.
- Custom Installation Manual
- Understanding that a well-documented product builds customer trust, Zetacadd designed and authored a user-friendly installation manual, complete with:
- Sequential diagrams for each assembly stage
- Tool and hardware lists tailored to end users
- Detailed steps for metal, wood, and composite finishes
- Guidance for optional add-ons like safety gates, inner handrails, and balcony railings
- This manual helped the client to provide a premium DIY experience with reduced support calls and better user satisfaction.
- Code & Safety Compliance
- We embedded regional compliance requirements directly into the design phase, referencing:
- L.A. Standard Plan #111
- California Building Code (2019 CBC)
- IRC stair safety standards for residential use
Every aspect of the stair—from riser height to spindle spacing—was validated for structural and regulatory integrity.
Result
• Reduced product launch time by streamlining design-to-documentation workflow
• Lowered manufacturing costs through optimized fabrication drawings
• Improved user satisfaction and assembly success with an intuitive manual
• Created a reusable platform for multiple stair variants and materials
Client Feedback
“Zetacadd played a key role in helping us bring a new stair product to life. Their engineering insight, attention to detail, and documentation quality made this launch one of the smoothest we’ve had.”