For EPC procurement teams, the drawing package is the foundation of a steel structure RFQ. If the package only includes a layout image or an early concept plan, suppliers may quote based on different assumptions. That makes prices hard to compare and increases the risk of later variation claims.
1. General arrangement drawings
General arrangement drawings show the building layout, grid lines, elevations, spans, bay spacing, eave height, ridge height, floor levels, and major structural zones. They help the supplier understand the project scale and the relationship between columns, beams, roof framing, mezzanines, crane beams, and envelope interfaces.
- Plan view with grid dimensions.
- Elevation views and roof slope.
- Building length, width, height, and bay spacing.
- Crane, platform, mezzanine, or special equipment zones.
2. Structural drawings and member schedules
Structural drawings allow the fabricator to understand steel member types, section sizes, connection locations, and estimated tonnage. If fabrication drawings are not ready, provide at least structural design drawings or a member schedule that states columns, beams, bracing, purlins, girts, and secondary steel.
| Drawing item | Why it matters |
|---|---|
| Column and beam layout | Defines primary steel quantity and fabrication complexity. |
| Connection details | Helps estimate plates, bolts, welding, drilling, and shop labor. |
| Purlin and girt layout | Clarifies secondary steel quantity and package scope. |
| Bracing layout | Shows stability system and site assembly requirements. |
3. Load and design basis information
Suppliers cannot safely confirm scope if the design basis is unclear. EPC buyers should identify the design code, wind load, snow load, seismic requirement, crane load, live load, and any project-specific owner standard. This is especially important when quotations are requested before final design approval.
4. Material, welding, and coating notes
The quotation should state material grades, bolt grades, welding standard, surface preparation grade, paint system, dry film thickness, galvanizing requirement, and color requirement. Missing coating notes often create large differences between quotes.
5. Interface drawings
Steel structure packages often connect with cladding, equipment foundations, conveyors, pipe racks, crane systems, doors, louvers, or civil works. If these interfaces are not shown, ask suppliers to list exclusions clearly instead of hiding assumptions in the price.
6. Minimum drawing package before quotation
- General arrangement drawings.
- Structural design drawings or member schedule.
- Connection intent or typical connection details.
- Material and coating specifications.
- Design code and load information.
- Scope boundary and exclusions.
- Destination country and delivery basis.
Buyer note
If the drawings are still preliminary, say so in the RFQ. Ask each supplier to separate firm pricing from provisional items. This makes the quotation easier to compare and reduces disputes after award.