Integrated building design, information and simulation modelling: the need for a new hierarchy

The need to reduce radically the energy used by buildings is leading to new design practices.  Current design and simulation software are used in very different ways, with energy simulation generally employed to check energy code compliance after the design stages are mostly finished.  This linear approach to working practices, the modelling methods used and poor interoperability inhibit iterative design practices.  This paper outlines a case study to elicit early software requirements for combined simulation and design software.  The barriers to this type of integrated software are discussed.  Finally, a change to the hierarchy of existing interoperable languages is proposed.