Light gauge steel design and detailing for single-family home in Chico

This project involves a two-story residential house distinctively characterized by its Quonset hut roofline, a lightweight prefabricated structure made of corrugated galvanized steel with a semi-cylindrical cross-section. The exterior and interior walls, as well as the first floor, are constructed using LGS framing.

ORIGIN was commissioned to create structural construction drawings and conduct a structural analysis of the LGS framing and foundation of the building. Given that the project’s builder owns a Framecad rollformer, the production of CNC files for LGS panels was also required.

Input: A set of architectural drawings.

Project Deliverables:

• Structural drawing set;
• Structural analysis report;
• LGS shop drawings;
• Framecad CNC files for LGS panel production.

The process begins with a thorough examination of the architectural drawings. A conceptual structural scheme is built in this phase, checking for structural viability and noting any issues for the architect’s review and adjustments. The PDF architectural drawings are then transformed into a clean Revit model, incorporating the foundation, floors, roofs, and walls as the basis for the forthcoming LGS framing.

Structural Modeling: After completing the Revit model, we initiate the LGS framing process using the Strucsoft MWF Advanced Metal software. This Revit plugin provides tools for the automated creation of LGS framing, factoring in the thicknesses of floors, roofs, walls, and openings. Following this, foundation modeling ensues.

After the preliminary structural modeling is completed, a comprehensive structural analysis is undertaken. Calculations for LGS framing are done using SciaEngineer software, while Excel and Mathcad spreadsheets are employed for masonry walls and foundation calculations.

Our calculations comply with the following codes:

• 2019 Edition of the International Building Code;
• 2019 Edition of the International Residential Code;
• ASCE 7-16: Minimum Design Loads and Associated Criteria for Buildings and Other Structures;
• Steel Design: AISC 360-10/05 (ASD);
• Cold-Formed Steel: AISI S100-16w;
• Seismic: AISC 341-10/05;
• Concrete: Reinforced Concrete Design Handbook (ACI);
• Ultimate Strength: Design Handbook (ACI);

At the end of this page, you will find a full structural report.

The validated LGS framing leads to the creation of Revit views like plans, sections, elevations, and details. The complete structural model negates the need for manual drawing, with the focus shifting to adding dimensions, annotations, and notes. The finalized plans are then submitted to the building department for approval.

Upon plan approval, the production of LGS panels begins, entailing the exportation of CNC files from the Revit model to the Framecad rollformer for the fabrication of profiles. The assembly of LGS panels from the members is aided by provided shop drawings, each labeled and dimensioned.