Sustainable building optimization – A systemic approach

Objective: During the last two decades various building sustainability certification systems have been developed and established. These assessment systems are considered to be appropriate tools for the evaluation of sustainability performance on buildings. Current building design optimisations mostly focus on single sustainability aspects like environmental quality or economic performance, disregarding a holistic approach. Investors strive to achieve a maximum of the assessment score on the one hand and optimized initial costs on the other. Project stakeholders usually have different points of view regarding project requirements and goals. Sustainable buildings – according to the upcoming CEN/TC 350 standards - should include environmental, social and economic aspects as well as functional and technical issues. In order to achieve a high performance concerning sustainability-assessment due to the choice of the right optimisation measures, early planning stages show the high potential (integral planning). Methods: Based on the Austrian building certification system (OGNI/DGNB), we applied a systemic approach for building sustainability-improvement, using a case study of a public office building in Graz, Austria. Results: The main part of our study describes six important steps required for systemic sustainability optimization. The applied method allows the quantification of the relative influence and the individual optimization potential of design options on each single assessment criterion. Conclusion: Building certification combined with a systemic approach regarding the interdependency between single criteria is an appropriate method for the improvement of building sustainability.