How to Calculate the Torsional Irregularity Ratio (TIR) by Hand: Verify Your ETABS Results | ASCE 7

ETABS reports a Torsional Irregularity Ratio, but how do you know the number is right? In this video, I calculate the TIR by hand from scratch, using real displacement values read from an 8-story ETABS model, and show that the manual result matches ETABS exactly (1.273 at Story 5). You'll see how to: ✅ Find the critical story and earthquake case in the ETABS table (Diaphragm Max Over Average Drift) ✅ Read the maximum and minimum joint displacements at the building edges ✅ Convert absolute displacements to story drift (Story 5 minus Story 4), the step that most often goes wrong ✅ Calculate the average drift and the final TIR in Excel, then verify it against ETABS Built for practicing structural engineers working with ASCE 7 and similar building codes. If you haven't seen the earlier videos, start with the concept of torsional irregularity and the ASCE 7 requirements (TIR limits of 1.2 and 1.4): ▶ Torsional irregularity, the concept: [   • Torsional Irregularity in Structures — Why...  ] ▶ TIR in ASCE 7 and ETABS: [   • Torsional Irregularity Ratio (TIR) Explain...  ] 📋 Want a free, step-by-step structural design checklist so you never miss a step in your projects? Get it here: [https://forms.gle/naoaxVJCRcxZNSko6] 📚 Reference: ASCE 7-22, Minimum Design Loads for Buildings and Other Structures, Section 12.3.2 Subscribe for more videos on structural and earthquake engineering: theory, code, and real ETABS modeling in one place. #StructuralEngineering #ETABS #ASCE7 #SeismicDesign #CivilEngineering