Milne Medal Lecture 2021: Less is More

The Milne Medal is awarded to an individual engineer for excellence in structural design, both in the overall concept and in the attention to detail in their work. The medal is named in recognition of the late Bob Milne, who served for many years as the Honorary Secretary of the IABSE British Group.

The 2021 Milne Medal was awarded to Margaret Cooke of Integral Engineering Design who specialises in the re-use of existing buildings. On the 9th November Margaret treated us to an inspiring lecture covering her work and posing challenges to all engineers in the future.

Margaret began by posing the question of how structural engineers can give the impression of value on projects where the skill is often making as few interventions as possible to a building. Through real life examples we were treated to vivid descriptions of the challenges of three projects.

The first example required visually inobtrusive engineering solutions to support the ongoing use of a historic building, noting that central to such works is careful understanding of the future use of the building to ensure the structural solutions are proportionate to need rather than purely to code requirements. A key theme raised in this example was that when dealing with historic buildings, designing the solution is the end point after the constraints are fully understood.

The second example was another historic building whereby understanding the owners needs and changing the use of individual areas major strengthening works were avoided. By asking why a space was used for storage, rather than how to make the floor strong enough, major works were avoided. A key theme in this example was the importance of the engineer taking time and making quiet space to understand the structure.

The final example was a more modern building renovation. At the heart of this example was that whilst the building required extensive modernisation to create a desirable workspace, the carbon cost of demolition and new build could not be justified. By applying careful renovation techniques to the structure, the quality of the building was enhanced without the carbon cost of new build. This example showed the power of using the skills and approach normally reserved for historic buildings on more recent building stock.

At the core of the presentation was the necessity of reuse of buildings to achieve net zero aims. This was backed up by numbers where the carbon footprint of the third example was between a third and a half of a best performing new build, with the minimal interventions of the second less than 10% that of a new build.

Returning to the original question, Margaret concluded that to show the value of minimal intervention structural engineering, the key throughout her career has been to take the client on the journey and make sure they are clear on the story of the work you are doing, but going forward the carbon story of doing nothing will be powerful and we must all strive to deliver this message.

The video of the lecture can be viewed here.