A New Approach to Sustainability – Green Adaptive Reuse: Professor Craig Langston

 

Vice-Chancellors’s Research Grant Scheme 2010/11 ($7,000)

Adaptive reuse is a powerful alternative to building demolition or destruction and can deliver a range of economic, social and environmental benefits to society that represent good value for money. It can extend the useful life of a facility through a change in function or purpose from that which previously applied and take advantage of the remaining physical life embedded in its materials and systems. When done well, the resultant projects are very successful, and much admired. This project explores the issues that surround adaptive reuse intervention and proposes a number of strategies that can enhance the possible benefits that flow from adoption of this approach in the context of a recent case study in Sydney, Australia. Adaptive reuse is important to our future in an era of climate change where maximizing wealth and utility must be tempered against minimizing resources and environmental impact. It is demonstrated that the concept of ‘green adaptive reuse’ is a valid strategy to both extend a facility’s life and reduce its carbon footprint, while helping to preserve important heritage values that define our cultural development over time. Coordinating adaptive reuse intervention with ‘greening’ initiatives can deliver opportunities for cost efficiency.

The case study is the former Bushells Tea Company building located in the historic ‘Rocks’ precinct of Sydney, Australia. Its name is 88 George Street. It was adaptively reused from two industrial warehouses constructed in 1886 and 1912 to commercial office space, and further extended in 1986. The conversion was completed in 2008. The building is Australia’s first example of a heritage-listed adaptive reuse project that has been awarded a 5-star Green Star rating by the Green Building Council of Australia, which is approximately equivalent to Gold LEED certification. It is the only known example of a successful heritage-listed green adaptive reuse conversion in Australia, using Green Star as a means of verification.

Information for this study was obtained from fieldwork and enquiries (primary data) and websites, brochures and magazine articles (secondary data). The owner and manager for the project is the Sydney Harbour Foreshore Authority. The design team comprised Terroir (project architect), Steensen Varming (mechanical/electrical engineer), Hooker Cockram (contractor), Design 5 (heritage), Warren Smith and Partners (hydraulic engineer), Chris Bylett and Associates (quantity surveyor), Simpson Design Associates (structural engineer), Trevor Howse (fire engineer), Acoustic Studio (acoustics) and Access Australia (DDA consultant).

First, the iconCUR model is used to determine whether adaptive reuse is the preferred strategy compared with other property management choices. Second, the ARP model is used to calculate the buildings useful life and potential for adaptive reuse. Third, the SINDEX model is used to validate whether the rework represents a sustainable decision and meets necessary compliance benchmarks. All three models are the result of earlier research by CI Langston and others.

The iconCUR model, applied prior to the redevelopment decision, suggests that adaptive reuse is the appropriate strategy. It calculates a condition rating of 3.55 (out of 5) and a utilization rating of 0.96 (out of 5), which places the project ‘nearby’ to the adaptive reuse corner of the matrix. It calculates a reward rating of 2.28 (out of 5) that suggests opportunity still remains to add value to this asset. Further investigation is recommended.

The ARP model further suggests that the timing for adaptive reuse was ideal (high and decreasing). A useful life of 94.6 years was predicted, indicating that the optimum intervention point was 2007. The ARP score of 75.4 is high, but it is now decreasing each year towards its expected end of life in 2112.

The SINDEX model computes a sustainability index of 3.49 using a balanced decision between economic (value for money) and social (quality of life) criteria. Value for money is defined as the ratio of ‘wealth’ to ‘resources’, while quality of life is defined as the ratio of ‘utility’ to ‘impact’. An overall sustainability index of 1 is the minimum acceptable score, but the higher the score the more attractive is the project. All minimum performance benchmarks are exceeded. The project’s redevelopment is therefore a feasible and sustainable proposition. Its environmental qualities have been confirmed in hindsight via the Green Star certification achieved.

All three of the evaluation models point to a consistent decision that also reflects what actually occurred. Adaptive reuse was the best strategy and there appeared opportunity to add value, the timing of the intervention was appropriate and the planned integration of adaptive reuse with environmental upgrade, given the particular confines of its heritage-listing, was convincing when financial, social and environmental criteria were combined. So the Sydney Harbour Foreshore Authority appear to have made a wise decision to proceed, and should expect many years of performance from this asset before any further interventions are required. Its prime location will ensure its commercial viability into the future.

This case study has demonstrated that adaptive reuse and exemplar environmental performance are not mutually exclusive. Through the coordination of facility conversion and environmental upgrade, cost efficiency is achieved. Heritage-listed buildings do not necessarily represent a barrier to this strategy. The additional cost normally expected from a building that meets high environmental performance benchmarks is offset by the opportunity to reuse existing structure and fabric via an adaptive reuse strategy. Interestingly these inclusions, which minimize ongoing operational costs into the future, may not have been viable with a new-build scenario.