The Most Expensive Structural Mistakes Happen Before Anyone Draws a Beam

Most people think structural engineers only get involved once the concept is done and it’s time to size the beams, columns and foundations. In New Zealand, especially with our highly active seismic environment, the biggest opportunities to save cost and reduce risk actually happen during the first 5–10% of the design process. This is where structural engineers have the most influence on the overall design philosophy, seismic behaviour and long-term performance of a large commercial building.

Figure 1: Illustration of structural influence and cost relationships across project design stages.

Here are a few things clients, architects and developers often tell us they “didn’t realise structural engineers could help with.” Each one has a significant impact on cost, buildability and performance.

1. Configuration Planning

The structural grid you lock in at concept stage controls everything, including:

• structural cost

• floor heights

• ceiling space

• seismic demands

• future fitouts

• crane access and staging

  
  

A well-planned grid can save hundreds of thousands in avoided structure, redesign or lengthening the construction programme.

2. Seismic Design Strategy

Small architectural changes such as shifted cores, varying floor heights, large overhangs or long spans can quietly drive up seismic forces and therefore cost. While these are often necessary to achieve the overall vision, they can markedly reduce the resilience and repairability of a building.

There are many structural systems and technologies available in NZ (e.g. base isolation, rocking/replaceable components, hybrid post-tensioned frames/walls, buckling-restrained braces). These options may bring a slight increase upfront or additional constraints for the building layout but can significantly improve performance and reduce downtime after an earthquake.

Early structural input keeps the form clean, efficient, buildable and compliant, without compromising design intent.

3. Foundations & Ground Risk Forecasting

Long before detailed design, we can predict whether you’re heading toward:

• simple pads and slabs, or

• a six-figure piling or ground improvement package.

This early foresight changes everything about budgeting, risk planning and feasibility, especially on variable or marginal ground common across NZ.

4. Construction Sequencing & Buildability

Small tweaks to column layout, shear wall placement or slab pour strategy can take weeks off the programme.

Early collaboration with contractors or fabricators can also remove unnecessary temporary works, reduce crane time and simplify erection.

5. Services Integration Made Easy

If the structure and services teams don’t coordinate early, you can end up with:

• ceiling-height issues

• riser clashes

• duct conflicts

• redesign

• late-stage delays

• frustrated contractors

A services-friendly structural layout avoids all of this.

The Key Takeaway

Bringing your Structural CPEng in early isn’t about designing beams sooner, it’s about setting the entire project up for success. It reduces redesign, avoids surprises, improves buildability and protects your budget from escalation later on. If you’re an architect or developer planning your next project, involve your structural engineer at concept stage, and consider whole-of-life cost and resilience from day one. It’s one of the highest-ROI decisions you and your client can make.