DR LISA OTTENHAUS IS A STRUCTURAL TIMBER ENGINEER, A LECTURER AT THE UNIVERSITY OF QUEENSLAND, AND PART OF THE FUTURE TIMBER HUB. LISA RESEARCHES AFFORDABLE MODULAR HOUSING.
How has your career path led you to engage with innovative timber solutions?
I’ve been studying timber for the past 10 years. During my PhD at the University of Canterbury in Christchurch, New Zealand, I researched the seismic behaviour of connections in CLT panels. During this research I found that CLT is a great material but it’s often cost-prohibitive. So I started to think about combining CLT core wall systems with light timber framing; modular offsite construction was the logical next step. This decision was reinforced when I started my position at UQ. Australia has unique challenges and opportunities that are quite different from other parts of the world and I believe that offsite construction can be an answer to a number of those challenges.
What are some of those challenges?
Most of Australia’s population is concentrated along the coast lines. With the current predictions for sea level rise most of our coastal cities will be underwater by the end of the century; yet waterfront properties are still highly sought after. If we don’t act soon, we will end up with a problem like Indonesia which is currently abandoning its capital Jakarta and relocating its population to higher lying islands. My research is centred around design for disassembly and relocation which – if you think about it – is really just a small addition to DfMA. Together with my colleague Dr Paola Leardini we look at developing flexible prefabricated building systems that can adapt to changing boundary conditions. These could be user imposed, for example expansion of a dwelling for a growing family, or external, such as increased bush fire and flooding risk, which may require relocation.
This means you could live in your waterfront property until the land it sits on is no longer insurable and then pack up your home and relocate to higher ground. Interestingly, after the Christchurch earthquakes, a number of the homes in the “red zone” had sustained minor structural damage. However, the land they were located on was uninsurable and therefore most of these dwellings were demolished. Only a fraction of the salvageable buildings were actually relocated. Imagine how much grief the owners could have been spared if these buildings had been designed modular and relocatable.
“My research is centred around design for disassembly and relocation which – if you think about it – is really just a small addition to DfMA. We look at developing flexible prefabricated building systems that can adapt to changing boundary conditions. These could be user imposed, for example expansion of a dwelling for a growing family, or external, such as increased bush fire and flooding risk, which may require relocation.”Dr Lisa Ottenhaus, lecturer, University of Queensland.
How does circular economy thinking feature in your research?
The circular economy framework weaves through all aspects of the research. Take design for disassembly; it is a key feature that is needed to transition our offsite construction industry to a circular model with the idea that we can reuse parts of the building over and over again, much like we are already doing in aviation. Aviation adopted component passports a long time ago and the state of each component of an aircraft is exactly known. Of course there are many questions around traceability, certification and reissuing of these building parts and we are currently working on that.
What’s your outlook on where Australia’s offsite construction industry is heading?
I hope clients and local governments will embrace prefab as the future of affordable and sustainable housing. I think there is a lot to be done to get builders and legislators on board and we need to invest into education of the broader industry. Targeted continuing professional development courses and other workshops for builders and interested AEC professionals would be a great place to start.■