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.