Source: https://www.quantumsteeldesign.com/videos/hss-nominal-vs-design-wall/ Steel video · 0:53 # Why 1/4-Inch HSS Uses a 0.233-Inch Design Wall See why a nominal 0.250-inch ASTM A500 HSS wall becomes a 0.233-inch design wall and how ASTM A1085 differs under current guidance. What you will learn - 0.250: Nominal wall thickness. - × 0.93: A500 design factor. - 0.233: Design wall thickness. Published August 6, 2026 [Watch on YouTube ↗](https://www.youtube.com/watch?v=22qlZkD1gt8) [Watch the Short ↗](https://www.youtube.com/shorts/k7eH-ic5nVc) Practical context ## How the steel information fits the project workflow When actual wall thickness is unknown, AISC tabulated A500 HSS properties use the reduced design thickness. The correct design thickness depends on the governing HSS material specification and project requirements. Continue with the data ### Steel shapes and properties Move from the video explanation to the related reference, dimensions, properties, tools, and learning context. [Open related reference](https://www.quantumsteeldesign.com/learning-hub/steel-shapes-and-properties/) Companion reading and practice ## Which thickness field are you actually reading? The video’s example distinguishes a 0.250 in nominal wall from a 0.233 in tabulated design wall. Copying the label into every thickness field would erase that distinction. Read the material specification, source edition, and field definitions before using a thickness. The example is not a universal rule for every HSS product or specification. Database design values and measured product dimensions also answer different questions. ### Try it with a sample Inspect tnom and tdes in an HSS record and keep both names and units with the copied values. [Inspect the two wall fields](https://www.quantumsteeldesign.com/steel-tools/shapes/hss6x6x-250/) Examples are fictional learning exercises. This companion text adds context to the video; the transcript below records the narration. Primary sources ## References and further reading - [AISC Shapes Database v16.0](https://www.aisc.org/aisc/publications/steel-construction-manual/aisc-shapes-database-v160/) - [AISC standards and specifications](https://www.aisc.org/aisc/publications/current-standards/) Use the edition and requirements adopted for the project. These references support further reading; a short video does not reproduce the complete standards. Published by Quantum Steel Design. [Sources and editorial approach](https://www.quantumsteeldesign.com/about/#editorial-approach) · [Report a correction](https://www.quantumsteeldesign.com/contact/) · Companion guide updated September 28, 2026. Accessible transcript ## Why 1/4-Inch HSS Uses a 0.233-Inch Design Wall transcript The visible transcript makes the video content available to people and search systems without requiring playback. - A quarter-inch H S S wall is not always a quarter inch in design calculations. - For A S T M A five hundred H S S, AISC uses a design wall thickness equal to zero point nine three times nominal when actual thickness is unknown. - Multiply point two five zero by point nine three. - That gives point two three three inches, the value tabulated for H S S six by six by one quarter. - This reduction is already reflected in the AISC tabulated section properties for A five hundred shapes. - A S T M A ten eighty-five is different. Full nominal thickness is used under the cited AISC and Steel Tube Institute guidance. - Always confirm the material specification, current code, and project requirements before calculating a member or connection. - Find more steel references and practical tools at Quantum Steel Design. Keep watching ## More structural steel detailing and fabrication videos. [View the complete video library](https://www.quantumsteeldesign.com/videos/) [0:50](https://www.quantumsteeldesign.com/videos/c-vs-mc-channels/) August 6, 2026Steel explainer ## C vs MC Steel Channels: What Is the Difference? Understand the difference between American Standard C channels and miscellaneous MC channels, including geometry, connection dimensions, properties, and substitutions. [Watch with transcript](https://www.quantumsteeldesign.com/videos/c-vs-mc-channels/) [Watch Short ↗](https://www.youtube.com/shorts/NRcTG7VhaA0) [11:50](https://www.quantumsteeldesign.com/videos/steel-project-handoff-release-control/) September 27, 2026Long-form field guide ## Steel Project Handoff: Submittals, Revisions, and Release Control Coordinate steel submittals, review comments, RFIs, revisions, partial releases, and fabrication data with a clear source baseline and documented handoff. [Watch with transcript](https://www.quantumsteeldesign.com/videos/steel-project-handoff-release-control/) [Watch on YouTube ↗](https://www.youtube.com/watch?v=21pkU1yMoZ8) [11:30](https://www.quantumsteeldesign.com/videos/structural-steel-takeoff-workflow/) September 27, 2026Long-form field guide ## Structural Steel Takeoff: From Drawings to a Defensible Material List Build a traceable structural steel takeoff: define scope, count members, label lengths and units, calculate nominal weight, document allowances, and compare revisions. [Watch with transcript](https://www.quantumsteeldesign.com/videos/structural-steel-takeoff-workflow/) [Watch on YouTube ↗](https://www.youtube.com/watch?v=Dv-RwOBNf-Y)