Hi marblaze
Following is a rough breakdown of the costs for a 25 metre (82 foot) span, 7 metre (23 foot) eave height, portal frame building, from Waston (1996), Costing of Steelwork from Feasibility Through to Completion,
Steel Construction, Vol 30 No 2:
[ul square]
[li]supply, 72%[/li]
[ul circle]
[li]steel, 20%[/li]
[li]purlins, 13%[/li]
[li]sheeting, 39%[/li]
[/ul]
[li]fabrication, 15%[/li]
[li]surface treatment, 2%[/li]
[li]erection, 11%[/li]
[ul circle]
[li]steel, 2%[/li]
[li]purlins, 4%[/li]
[li]sheeting, 5%[/li]
[/ul]
[/ul]
Having a structural engineering background, the main tips that I can give you are:
[ul]
[li]keep the structure simple, e.g. standardise bay widths[/li]
[li]give careful consideration to selection of purlins and sheeting[/li]
[li]rationalise member sizes[/li]
[li]maximise shop fabrication and minimise field welding[/li]
[li]keep the connections simple, e.g. minimise number of connection components; minimise use of stiffeners[/li]
[li]standardise connection geometry and elements, e.g. one bolt size, grade and tightening procedure; one electrode strength grade, weld category and weld size (if possible)[/li]
[/ul]
Also, see the following papers from the Structural Steel Education Council (
[ul]
[li]Cost Considerations for Steel Moment Frame Connections[/li]
[li]Value Engineering and Steel Economy[/li]
[li]What Design Engineers Can Do To Reduce Fabrication Costs[/li]
[li]Designing for Cost Effective Fabrication[/li]
[/ul]