The objective.

This remediation of the Executive Wing, a Category 1 Heritage building, required carefully balancing structural upgrades with preservation of heritage features.

The project involved replacing large lower windows held by curved steel frames, fixed to concrete bays, with minimal disruption to heritage tiles surrounding the frames. A total of 36 frames were manufactured and installed under strict preservation conditions.

Our involvement.

Petone Engineering led the fabrication and installation of rigid yet flexible steel frames to support the double-glazed windows. Steel was chosen for its ability to bear heavy loads while accommodating seismic movement, ensuring that the glass would not experience damaging forces during an earthquake.

Each bay’s unique dimensions necessitated precise site measurements, which were modelled using Tekla software to streamline fabrication and produce customised frames within a two-week turnaround. An innovative design improvement using solid steel blocks reduced welding complexity and enhanced frame aesthetics.

The outcome.

This project preserved the Beehive’s heritage aesthetics while reinforcing its structural integrity.

Original frames were recycled as scrap, and removed tiles were reinstalled, minimising waste. The seismic-friendly frames achieved both a robust and flexible design, safeguarding the glass in the event of seismic activity and allowing the project to finish on schedule with reduced fabrication time and improved visual results.