Direct Answer
The critical path for most steel projects runs: design documents → detailing start → detailing complete → submittal → engineer review → IFC approval → material delivery → fabrication → shipping → erection. The longest chains are usually detailing (6–10 weeks) and material lead time (4–16 weeks for long-lead sections) — both begin before IFC approval, which requires deliberate overlap management.
Full Explanation
On a typical 200-ton commercial project, the schedule might look like: Week 1–2 (design documents received, detailing starts, preliminary BOM issued, material order placed), Week 2–8 (detailing ongoing, anchor bolt plan issued at week 3, approved week 5), Week 8–10 (first submittal), Week 10–13 (review), Week 13–14 (IFC approval), Week 12–16 (material arrives), Week 14–22 (fabrication), Week 20–28 (erection). Compressing this schedule requires parallel tracking: ordering material on the preliminary BOM before IFC, and potentially starting fabrication on approved-anchor-bolt and simple beam drawings before complex connections are approved.
What This Means for Your Shop
The GC's project schedule almost never accounts correctly for the full detailing and fabrication lead time. Your job is to make this timeline visible at the pre-construction meeting and get GC buy-in on a realistic steel delivery date.
Common Mistakes
Accepting a GC's schedule that shows 'steel start' four weeks after contract award. Four weeks is insufficient for detailing, approval, and material procurement on any project of meaningful scale.
Recommended Process
At project kickoff, build a detailed schedule showing the critical path for steel from design document receipt to erection complete. Present it to the GC and get signature acceptance. Use this as the baseline for any delay or acceleration claims.