The latest European Union directive on public procurement proposes that contracts for the procurement of buildings should be awarded according to life cycle costing, taking into account external environmental impacts. 
The developed cost model (LCA-based bonus/malus system) for the procurement of buildings enables the application of life cycle assessment (LCA) considering the environmental building performance in the award decision. Using the method of environmental life cycle costing, building-related greenhouse gas emissions are monetised and integrated into the bid prices in the form of external costs and a greenhouse gas emission bonus/malus. 
In addition, a systemic planning model (hierarchical reference-based know-why model) is used to identify interactions between planning decisions and thus support the implementation of a future LCA-optimised planning process for more environmentally friendly building procurement. 
The development of the presented models lays the foundations for further implementation steps of a more environmentally friendly building procurement process in Austria.