Sustainability in technical design: from world goals to LCA

According to the training regulations, a technical designer must be able to contribute to ensuring environment and sustainability in technical design solutions based on knowledge of the UN's 17 Sustainable Development Goals. It is not a ceremonial phrase: in both industry and construction, climate and environmental requirements are today concrete numbers that must be calculated and documented — and documentation is precisely your trade.

The UN's 17 Sustainable Development Goals were adopted in 2015 as a common agenda towards 2030. For a technical designer goals on sustainable industry and innovation responsible consumption and production and climate action are particularly relevant: In practice they translate to questions like — can the design be made with less material? Can it be disassembled and recycled? Can a lighter design save energy throughout the product's lifetime?

In construction, the requirements have become mandatory: since 1 January 2023, the Danish Building Regulations BR18 have required a climate calculation — a life cycle assessment (LCA) — for new buildings. The first limit value was 12 kg CO₂ equivalents per m² per year and applied only to new buildings over 1,000 m². From 1 July 2025 the requirements were tightened and differentiated: the LCA requirement now also covers smaller buildings and extensions (with few exceptions), and the limit value depends on the building type — 4.0 kg CO₂e per m² per year for holiday homes under 150 m², 6.7 for detached and terraced houses, 7.5 for apartment buildings, offices, retail and warehouses and 8.0 for other buildings (BR18 § 298, subsection 1). In addition, a separate limit of 1.5 kg CO₂e per m² per year has been introduced for the construction process itself (§ 298, subsection 5). Always check the current wording of the building regulations. This means that choosing materials is no longer only about price and strength, but also about documented climate footprint.

Here the technical designer becomes central: An LCA requires quantities — how many cubic meters of concrete, tons of steel and square meters of insulation does the project contain? Those quantities are drawn from the BIM model, and the calculation is never better than the model behind it. Incorrectly classified objects, duplicates or missing building parts give incorrect climate figures. Precise modeling and correct property data have thus become a climate competence.

• 01Model building components with correct material and classification so quantity extraction can be mapped to climate data.
• 02Keep the model in sync with the project — an outdated model gives an outdated climate calculation.
• 03Save the basis: which EPDs and assumptions were included in the calculation, and which version of the model was used.
• 04Think disassembly: joints with bolts rather than glue make component reuse possible.

Experience from both industry and construction shows that the vast majority of a product's environmental impact is determined in the early design phases — when geometry, materials and production method are chosen. Later you can only optimise on a small scale. Therefore sustainability belongs in the sketch phase: a leaner cross-section, a recycled material or a construction that can be repaired instead of replaced, is drawn in from the start. It is the designer at the keyboard who concretely makes the difference — one parametric change at a time.

“The most sustainable material is the one you don't need to use.”

— Basic principle in material-saving design