Who Initiates Field Revisions
Field revisions are initiated by the erection superintendent, the GC's field engineer, or the fabricator's field representative. The initiation typically takes the form of a field RFI or a written request to the detailer and GC: 'Member B-304 at grid D4 does not fit due to [condition]. Requesting revised drawing to show [proposed change].' The request should include a sketch of the existing condition and the proposed resolution.
The Routing and Response Chain
Field revision requests route from the field through the GC to the detailing PM. If the revision requires engineering input (a structural change, a new connection type), it goes to the EOR simultaneously. The detailing PM should acknowledge receipt within hours and provide an estimated turnaround time. On urgent changes that are holding the crane, turnaround times of 24–48 hours are typically expected — a standard that Tectonix's two-shift production model is specifically designed to support.
Documenting Field Revisions in the Drawing Set
All field revisions must be incorporated into the drawing set as a new revision — not resolved informally and forgotten. The revised drawing should show what changed, with revision clouds, a new revision letter, and a note referencing the field condition or GC direction that triggered the revision. The as-built model must be updated to match. At project closeout, the final drawing set and as-built model should reflect all field revisions, not just the original fabrication package.
Engineering Authority for Field Revisions
Not all field revisions are equal in terms of who can authorize the change. A revision that affects only non-structural dimensions — a bolt hole shifted within AISC tolerance, a weld access hole resized within AWS D1.1 limits — can be authorized by the detailing PM. A revision that changes a connection type, alters a member size, adds a new load path, or affects a seismic-resisting system requires EOR input before the drawing is revised. The detailer's role in field revisions is execution — building and issuing the revised drawing — not making engineering decisions. Revisions that were made by field workers without EOR authorization and then documented after the fact as detailer revisions are a legal and professional liability problem that detailers must refuse.
Urgent vs. Non-Urgent Field Revisions
Field revisions fall into two urgency categories based on whether erection is on hold. Urgent revisions — where the crane and crew are standing — require same-day or next-morning turnaround. The detailer must interrupt other work, escalate to the EOR if engineering input is needed, and issue a revised drawing or field sketch within the shortest achievable timeframe. Non-urgent revisions — where the affected member has not yet been erected and time remains before it is needed — follow the normal revision cycle: model update, drawing extraction, QA check, issue. Fabricators and GCs should communicate the urgency level when requesting field revisions, so the detailer can appropriately prioritize.
How Field Revisions Affect the BOM and Material
Field revisions that change a member's dimensions, section size, or material grade also affect the BOM. If a revision shortens a member, the as-fabricated BOM should reflect the actual cut length — not the original drawing length. If a member is replaced entirely with a different section, the BOM must add the new member and remove the original. These BOM updates affect shipping manifests, payment applications (for weight-based contracts), and the as-built documentation the owner receives at closeout. Treating field revisions as drawing-only changes without updating the model and BOM creates a growing discrepancy between the project's documentation and the steel that was actually installed.
Post-Revision Inspection Requirements
Field revisions that affect structural connections may trigger special inspection requirements under IBC Chapter 17. A field-welded modification to a moment connection, an added stiffener plate, or a field-drilled hole in a seismic frame member may require the special inspector to observe and document the work before it is concealed by fireproofing or other finishes. The detailer should flag any revised drawing that affects inspectable structural work with a note identifying the inspection requirement. Failing to notify the special inspector of a field modification that required inspection observation creates a condition that may require destructive investigation to verify retroactively.