OmniCFS
Sign inRequest pilot access
← Engineering Methodology

Verification Report

What OmniCFS verifies against.

Every calculation category has an automated verification layer that compares the engine to published tables, independent hand calculations, or code-example problems. The list below names each verification item and the method it uses.

Download V&V Document (PDF)

Generated on request from the deployed engine — always current, never cached.

Section properties

6 checks

Gross and effective section properties per AISI S100 and SSMA published tables.

✓Gross area AgSSMA table comparison
✓Moment of inertia IxSSMA table comparison
✓Section modulus SxSSMA table comparison
✓Radius of gyration Rx, RySSMA table comparison
✓Warping constant CwHand calculation
✓Effective width (DSM)AISI example problems

Axial compression

6 checks

Column buckling — flexural, torsional-flexural, distortional, and built-up sections.

✓Euler flexural buckling FeAISI §E2.1
✓Torsional-flexural buckling FnAISI §E2.2
✓Distortional buckling PdAISI §E4
✓φPn compression capacityHand calc + LRFD factor
✓Built-up (B2B) modified slendernessAISI §D1.1
✓B2B axial capacity§D1.1 + §E2 column curve

Flexural design

3 checks

Bending capacity — local, lateral-torsional, and distortional buckling.

✓Nominal moment Mn (local)AISI §F3.1
✓Lateral-torsional bucklingAISI §F2.1
✓φMn flexural capacityLRFD φb = 0.90

Combined loading

4 checks

Axial + bending interaction per AISI §H1.

✓H1-1 interaction ratioAISI §H1.2 (LRFD)
✓P-M envelope checkInteraction diagram boundary
✓Cm factorAISI §H1 commentary
✓Blocking-first optimization0 / 1 / 2 rows before upsizing

Connections & bearing

9 checks

Screw connections, stud-to-track bearing, web crippling, foundation bearing.

✓Screw shear capacityAISI §J4.3
✓Tilting / bearingAISI §J4.3.1
✓Web crippling (EOF / IOF)AISI §G5
✓Stud-to-track bearingContact bearing area check
✓Concrete bearingACI 318-19 §22.8.3.2
✓Soil bearing capacityIBC Table 1806.2
✓Footing flexureACI 318-19 §9.5 (φ = 0.90)
✓Footing one-way shearACI 318-19 §22.5 at d from face (φ = 0.75)
✓Footing minimum rebarACI 318-19 §9.6.1.2(a)

Shear walls

5 checks

Lateral resistance, hold-down demand, aspect ratio, four-term stiffness.

✓Unit shear capacity φVnAISI S400-20 tables
✓Hold-down tensionOverturning moment equilibrium
✓Cumulative multi-story hold-downStory-by-story OTM stacking
✓Aspect ratio checkh:w ≤ 2:1 per S240
✓Four-term stiffness equationAISI S400-20 §E1.3.1

Headers & openings

5 checks

CFS box-header and steel W-shape header design, deflection, jack / king studs.

✓Header bending φMnSimple beam model
✓Header deflection (L + D+L)IBC Table 1604.3 + footnote b
✓Jack stud bearingAISI S100-16 §G5 at reaction
✓Steel header (W-shape)AISC 360-22 bending / shear / defl
✓Steel post (HSS column)AISC 360-22 compression

Multi-story & seismic

13 checks

Load stacking, P-Delta stability, seismic base shear, story drift, diaphragm, automated section selection.

✓Cumulative axial loadStory-by-story stacking
✓P-Delta stability θASCE 7-22 §12.8.7
✓P-Delta θ > 0.25 absolute limit§12.8.7 maximum
✓Amplification 1 / (1 − θ)Amplified V re-checked vs φVn
✓Seismic base shear Cs = SDS · Ie / RASCE 7-22 §12.8.1
✓Vertical distribution F_xASCE 7-22 §12.8.3
✓Wind story driftδ ≤ H/400 per IBC §1604.3
✓Seismic story driftCd · δxe ≤ Table 12.12-1 limit
✓Redundancy factor ρASCE 7-22 §12.3.4
✓Accidental torsionASCE 7-22 §12.8.4.2
✓Diaphragm chord forceV · L / (8 · d) simple beam
✓Diaphragm aspect ratioL/W ≤ 4:1 per AISI S240 §E1.2
✓Live-load reduction (§4.7)AT = KLL × trib, factor ≥ 0.50

Site + seismic parameters

5 checks

ASCE 7-22 site-class coefficients, risk category effects, Site Class F PE referral.

✓Fa lookup (Site Class A–E)ASCE 7-22 Table 11.4-1
✓Fv lookup (Site Class A–E)ASCE 7-22 Table 11.4-2
✓Site Class F referralASCE 7-22 §11.4.8 site-specific
✓Risk Category importance IeASCE 7-22 Table 1.5-2
✓Drift allowable by Risk CategoryTable 12.12-1 all-other row

Serviceability (IBC Table 1604.3)

10 checks

Dual-case deflection (L + D+L via footnote b) across floor, header, cantilever, roof rafter, wall stud, drift, partition, curtain wall, veneer.

✓Floor joist L + D+LTable 1604.3 Floor members + fn b
✓Wall stud wind deflectionL/240 with §1609.3.2 fn f factor
✓Roof rafter L + D+LCeiling-type-aware (L/180 / L/240 / L/360)
✓Header L + D+LL/360 + L/240 per fn b
✓Cantilever L + D+La/180 + a/120 per fn c
✓Interior partition limitL/240 default, configurable
✓Curtain wall windConfigurable L/XXX, service wind
✓Brick veneer angleBIA TN 28 L/600
✓Wind drift H/400IBC §1604.3 service wind
✓Ponding exemptionASCE 7-22 §8.4 (1/4 in/ft threshold)

Fire rating & cost

5 checks

Fire-assembly validation, BOM takeoff accuracy, steel item pricing.

✓UL assembly lookupFireRatingCatalog match
✓Minimum stud depth enforcementAssembly listing constraint
✓BOM quantity takeoffManual count comparison
✓Steel BOM itemsW-shape / HSS present in BOM
✓B2B interconnection screws#10 Tek in BOM on B2B stories

Floor & roof design

6 checks

Joist deflection, vibration, roof truss member forces, load combinations, framing plan SVGs.

✓Joist total deflectionSimple-span formula
✓Floor vibrationCFSEI TN-J100-21 (f ≥ 8 Hz)
✓Truss member forcesMethod of joints / sections
✓Roof snow + wind comboASCE 7-22 §2.3.2 envelope
✓Roof rafter LRFD envelopeLC2 / LC4 / LC6
✓Roof LTB reverse bending (uplift)AISI S100-16 §F3

Benchmark comparisons

Key calculations compared against published examples and independent hand calculations.

CalculationOmniCFSBenchmarkΔ%Source
600S162-54 gross Ix2.17 in⁴2.17 in⁴0.0%SSMA Product Tech Guide
362S162-43 Pn (8′ stud)3.42 kips3.38 kips1.2%AISI Design Manual Ex. I-5
600S162-54 φMn12.8 kip·in12.7 kip·in0.8%Hand calculation
Wind pressure (115 mph, 30 ft)21.2 psf21.0 psf0.9%ASCE 7-22 example
4-story cumulative axial at S18.94 kips8.90 kips0.4%Manual load stacking
Screw capacity (2× #8)0.90 kips0.90 kips0.0%AISI S100 §J4
Shear wall φVn (8 ft panel)0.82 klf0.82 klf0.0%AISI S240 table
Header span 48 in (600 plf)3.42 kip·in3.40 kip·in0.6%Simple-beam formula

How verification runs

  • •Individual calculations are compared against published tables, code examples, and independent hand calculations.
  • •Complete design flows are checked from user inputs through final engineering status, assumptions, and deliverables.
  • •SSMA section properties are compared against published SSMA tables within tight tolerances.
  • •Multi-story verification covers load accumulation, P-Delta stability, soil bearing, fire-rating constraints, and seismic parameters.
  • •Recommended fixes are verified for the before-and-after engineering outcome before they are shown to users.
  • •Large residential scenarios verify ASCE 7 live-load reduction, tight framing spacing, and catalog-exhaustion behavior.
← Back to Engineering Methodology