The Four Phases of a Detailing Engagement
Every project moves through four phases, each with its own duration drivers:
- Phase 1 — Model Setup (2–5 days): grid setup, column layout, member section assignment, and structural import from EOR Revit or DWG files
- Phase 2 — Detailing (variable): modeling all connections, miscellaneous steel, copes, embeds, and producing the drawing set
- Phase 3 — Internal QA/QC (2–5 days): cross-check of drawings against model, dimension verification, code compliance review
- Phase 4 — Submittal Cycle (2–6 weeks): EOR reviews drawings, issues comments, detailer revises, resubmit for final approval
Typical Durations by Project Size
General benchmarks for structural-only scope (miscellaneous steel adds 20–40% to Phase 2):
- Small commercial (under 200 tons): 3–5 weeks start to first submittal
- Mid-size commercial or industrial (200–1,000 tons): 6–10 weeks
- Large industrial or healthcare (1,000–3,000 tons): 10–18 weeks
- Phased or fast-track projects: first zone drawings in 3–4 weeks, remaining phases rolling
What Extends the Timeline
The most common schedule killers — all preventable:
- Incomplete IFC/DWG input: if the EOR issues structural drawings in multiple revisions during detailing, the model must be updated each time
- Undefined connection design responsibility: unresolved 'design by fabricator vs. EOR' decisions stall connection detailing
- Slow EOR review: the submittal clock stops when the drawings leave the detailer's office and restarts when comments arrive
- Change orders mid-flight: scope additions after detailing has started require re-sequencing — always carry a 2-week buffer for additive changes
- Missing architectural or MEP drawings: openings, embedded plates, and ceiling clearances can force cope or haunch changes after members are already modeled
Fast-Track and Phased Detailing
For projects where the fabrication schedule cannot wait for full drawing completion, phased detailing releases drawings in zones — foundations and anchor bolts first, then low-rise steel, then upper floors — allowing the shop to start fabrication while upper-level detailing continues. Tectonix runs a two-shift production model that makes phased detailing practical: night-shift progress means drawings advance even when your PM is off the clock.
The Submittal Review Cycle
The EOR's contract typically allows 10–14 business days per review cycle, though many structural engineers turn comments faster. Plan for two review cycles minimum: one for general comments (connection type, member orientation, scope items missed) and one for minor revisions after those are resolved. Projects with unusual structures, seismic detailing, or SMRF connections often require a third cycle. Fabrication cannot begin on stamped drawings until the EOR issues 'Approved' or 'Approved as Noted' — never on 'Revise and Resubmit.'
How to Protect Your Schedule
The clients who consistently hit their fabrication start dates do three things before detailing kicks off:
- Issue a complete and stamped set of structural drawings — not a permit-set-only package
- Resolve all connection design responsibility questions in writing before kickoff
- Provide architectural and MEP drawings even if they are still in development — a 60% MEP set is infinitely more useful than no MEP set