# Interoperability between Building Information Modelling (BIM) and Building Energy Model (BEM)
## 3 Results and Discussion
### Evaluation of the Processes  
As this article aims to evaluate the interoperability of BIM to BEM, all the processes are summarized in Table 4, in order to determine which one is the most feasible to implement in a daily office routine, under the vision of an architect user of the softwares. The feasibility was analysed according to the time spent, the effort dedicated, and the difficulty presented in each process, rated on a scale from 1 to 5, where 1 represents the easiest process and 5 represents the most difficult. This analysis was made according to a generic model which had a complexity level similar to that of the warehouse case.  
As can be seen from Table 4, exporting to the gbXML file was considered easier than the IFC format. At the moment of exporting the IFC from Revit, some specific parameters must be set correctly; otherwise, it cannot extract the data properly.  
\begin{table}
\begin{tabular}{l c c c c c} \hline \hline  & \multicolumn{2}{c}{**Export**} & \multicolumn{2}{c}{**Import**} & \\
**Process** & \multicolumn{2}{c}{**Revit**} & \multicolumn{2}{c}{**Design Builder**} & \multicolumn{2}{c}{**Open Studio**} & \multicolumn{2}{c}{**CYPHER HE**} \\  & **gbXML** & \multicolumn{2}{c}{**IFC**} & \multicolumn{2}{c}{**gbXML**} & \multicolumn{2}{c}{**gbXML**} & \multicolumn{2}{c}{**IFC**} \\ \hline Export/Import the files & 3 & 3 & 1 & 1 & 1 \\ Verify the information transferred & - & - & 4 & 4 & 3 \\ Correct the dimension errors & - & - & 3 & 5 & 5 \\ Correct the geometry errors & - & - & 3 & 5 & 5 \\ Correct the material errors & - & - & 3 & 3 & 2 \\ \hline Total & 3 & 3 & 14 & 18 & 16 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Comparative table with assessment of the processes. Scale range: 1 to 5, where 1 means the most feasible.  
\begin{table}
\begin{tabular}{l c c} \hline \hline  & \multicolumn{2}{c}{**CYPHER HE**} \\ \hline
**Process** & \multicolumn{2}{c}{**Export**} & \multicolumn{2}{c}{**Import**} \\
**Process** & \multicolumn{2}{c}{**Revit**} & \multicolumn{2}{c}{**Design Builder**} & \multicolumn{2}{c}{**Open Studio**} & \multicolumn{2}{c}{**CYPHER HE**} \\  & **gbXML** & \multicolumn{2}{c}{**IFC**} & \multicolumn{2}{c}{**gbXML**} & \multicolumn{2}{c}{**gbXML**} & \multicolumn{2}{c}{**IFC**} \\ \hline Export/Import the files & 3 & 3 & 1 & 1 & 1 \\ Verify the information transferred & - & - & 4 & 4 & 3 \\ Correct the dimension errors & - & - & 3 & 5 & 5 \\ Correct the geometry errors & - & - & 3 & 5 & 5 \\ Correct the material errors & - & - & 3 & 3 & 2 \\ \hline Total & 3 & 3 & 14 & 18 & 16 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Comparative table with assessment of the processes. Scale range: 1 to 5, where 1 means the most feasible.  
\begin{table}
\begin{tabular}{l c c} \hline \hline  & \multicolumn{2}{c}{**CYPHER HE**} \\ \hline
**Process** & \multicolumn{2}{c}{**Export**} & \multicolumn{2}{c}{**Import**} \\
**Process** & \multicolumn{2}{c}{**Revit**} & \multicolumn{2}{c}{**Design Builder**} & \multicolumn{2}{c}{**Open Studio**} & \multicolumn{2}{c}{**CYPHER HE**} \\  & **gbXML** & \multicolumn{2}{c}{**IFC**} & \multicolumn{2}{c}{**gbXML**} & \multicolumn{2}{c}{**gbXML**} & \multicolumn{2}{c}{**IFC**} \\ \hline Export/Import the files & 3 & 3 & 1 & 1 & 1 \\ Verify the information transferred & - & - & 4 & 4 & 3 \\ Correct the dimension errors & - & - & 3 & 5 & 5 \\ Correct the geometry errors & - & - & 3 & 5 & 5 \\ Correct the material errors & - & - & 3 & 3 & 2 \\ \hline Total & 3 & 3 & 14 & 18 & 16 \\ \hline \hline \end{tabular}
\end{table}
Table 3: _Cont._In turn, in the BEM softwares, importing the gbXML and IFC did not present any difficulty, as long as the interface at the time of import was correctly defined in the energy tool. The interoperability in Design Builder was considered the most feasible one and that in Open Studio was the least viable.