Case Study: Reducing Steel Structure Costs by 20%

Based on data from the UTMK Technical Department

Every extra ton of metal in an estimate is money spent unnecessarily by the client. But reducing metal consumption does not mean weakening the structure. This case study demonstrates exactly how this works in practice: a real project, specific figures, and four optimization steps.

Initial Project Data

The client was building a single-story commercial frame building: steel columns, girders, and bracings. The initial structural calculation was performed by a third-party company.

When the UTMK technical department reviewed the specification, four systemic issues were found:

• Profile tubes with excessive cross-sections — a "just in case" margin.
• Inflated safety factors without proper technical justification.
• Use of expensive steel grades where standard structural steels (e.g., S235JR according to EN 10025-2) are perfectly sufficient.
• The wall thickness of the profiles exceeded the standard values for this type of operational loads.

Together, these factors increased total metal consumption by 15–20% compared to similar standard facilities. In other words, the client was paying for extra metal the structure completely did not need.

Four Optimization Steps

1. Repeated Structural Analysis

The engineering team recalculated the supporting elements in accordance with the requirements of Eurocode 3 (EN 1993 for the design of steel structures) and relevant load standards (EN 1991). As a result, the following was found:

• Column cross-sections were oversized by 1–2 standard sizes.
• Stiffening elements were duplicated without any additional effect on spatial stability.
• Wind and snow loads were calculated based on outdated assumptions and zoning maps.

Incorrect initial loads are the most common cause of excessive metal consumption. Overestimating wind loads by 20% typically results in +15% of metal in the specification.

2. Replacing Profiles with Optimal Alternatives

Some heavy hot-rolled I-beams were replaced with:

• Cold-formed channels in secondary structural zones.
• Hollow section profile tubes (EN 10219) with a smaller wall thickness.
• More economical standard sizes, strictly maintaining the calculated rigidity of the joints.

The principle is straightforward: instead of simply increasing the wall thickness, engineers optimized the geometry — adding more braces and applying a correct anchoring scheme. The bearing capacity remains the same, but significantly less metal is required.

3. Optimization of Joints and Connections

Precise calculation of welded and bolted connections (according to EN 1993-1-8) allowed the team to:

• Reduce the total length of weld seams.
• Decrease the number of structural bolts.
• Lower installation labor costs without the slightest reduction in the frame's bearing capacity.

4. Unification of Standard Sizes

Instead of 8 different profile sizes, 4 unified ones were used on the site. This radically reduced:

• Costs for metal cutting and preparation.
• Logistical complexity (fewer items in the final order).
• Installation time — the crew does not waste time switching between different parts.

Results: After Optimization

Breakdown of savings by element groups:

Calculation: 42.5 − 34.1 = 8.4 t → 8.4 / 42.5 = 19.8% ≈ 20%.

Financial Impact

The financial effect directly depends on the current market price of rolled metal. Here are approximate calculations for different price levels (adapted for the European market):

This represents only direct savings on materials. There are additional benefits that are difficult to quantify in a table:

• Lower tonnage → lower transportation costs.
• Fewer standard sizes → simplified logistics and storage on the construction site.
• Shorter weld seams → reduced costs for electrodes and welding materials.
• Faster installation → earlier commissioning of the facility.

Why Excessive Metal Consumption is a Systemic Problem

Most projects with inflated estimated costs share one common cause: the initial calculation was performed "with a safety margin" without specific engineering justification. The logic is understandable — designers prefer to play it safe. But in steel structures, any excessive "margin" costs the client dearly.

Five basic questions to ask yourself before finally approving a specification:

1. Have the initial loads (wind, snow, payload) been verified against current EN standards?
2. Does the column effective length factor (K) truly correspond to the actual structural scheme?
3. Are spatial stiffness elements duplicated unnecessarily?
4. Are standard sizes unified, or was each element "selected individually"?
5. Are the lengths of the ordered elements calculated in multiples of standard lengths (e.g., 6 or 12 meters) to minimize offcuts?

If the answer to at least two questions is "not checked," the specification likely hides a solid reserve for optimization.

Conclusion

Optimizing a steel structure is by no means saving on quality. It is the technically sound elimination of excesses that arose solely due to inaccurate or overly cautious calculations. In this case study, correct handling of standard loads, competent selection of cross-sections, and unification of elements provided a 20% saving — without the slightest risk to the strength of the facility.

If you need a professional audit of an existing estimate or a competent selection of profile tubes according to European standards, contact the UTMK technical department. We operate in Europe, Poland, Bulgaria, and provide reliable delivery across the EU.