## 4 Results and Discussion
### Identification of Gaps Related to the Integration of EPD Data in IFC
\begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**IFC Property Type** & **Definition** & **Analogous Data Type** & \multicolumn{2}{c}{**Example**} \\ \cline{2-2}  & & **Data Type** & \multicolumn{2}{c}{**Property Name**} & \multicolumn{1}{p{113.8 pt}}{**Property Value**} \\ \hline \hline \multirow{2}{*}{IfcProperty SingleValue} & A property which has a single (numeric or descriptive) value assigned. & Scalar, text, number & WaterConumption & \multirow{2}{*}{20} \\ \hline \hline \multirow{2}{*}{IfcProperty BoundedValue} & A property which has a value assigned that is chosen from an enumeration. & List, 1-D array & StructureIn indicator & [COATED; COMPOSITE; HOMOGENEOUS \\ \hline \hline \multirow{4}{*}{IfcProperty BoundedValue} & A property which has a maximum of two (numeric or descriptive) values assigned, the first value specifying the upper bound and the second value specifying the lower bound. & List with 2 or 3 values, range & OverallHeight OverallWidth & [1200;900] \\ \hline \hline \multirow{4}{*}{IfcProperty ListValue} & A property that has several (numeric or descriptive) values assigned which are given by an ordered list. & List, 1-D array & ApplicableSize & [3200;6400;9600] \\ \hline \hline \multirow{4}{*}{IfcProperty ReferenceValue} & A property value to be of type of a resource level entity via the _fcObjectReferenceSelect_ types (e.g., IfcTable). & Scalar, number, text, 1-D or 2-D array; dictionary & GWPtotal ADPF & \{GWPtotal:[445,614,16,7,3,\(-\)12], ADPF:[4210,81,241,101,78,\(-\)116]] \\ \hline \hline \multirow{4}{*}{IfcProperty TableValue} & A property with a value range defined by a property object which has two lists of (numeric or descriptive) values assigned. & Limited 1-D or 2-D array & SoundTrans missionLoss & [[100;200;400], [20;42;46]] \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Definition of the properties in IFC. \begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline
**EN 15804:2012+A2:2019** & \begin{tabular}{} \end{tabular} & \
\begin{tabular}{} \end{tabular} &
\begin{tabular}{} \end{tabular} \\ \hline A4 Transport to the construction site & A4.1 and A4.2, for transport to the construction site [3] & It can be PRODUCTIONTRANSPORT. A specific element should be defined to avoid ambiguity \\ \hline A5 Installation into the construction asset & A5.1, A5.2, A5.3 and A5.4, for unsitallation and construction onsite activities [4] & INSTALLATION \\ \hline B1 Use of the asset & B1.1 and B1.2 for the use of the installed products [5] & It can be USAGE or OPERATION, but the stages may also include B6 or B7. Therefore, a specific element should be defined. \\ \hline B2 Maintenance & As in EN 15804+A2 & MAINTENANCE \\ \hline B3 Repair & As in EN 15804+A2 & REPAIR \\ \hline B4 Replacement & As in EN 15804+A2 & REPLACEMENT \\ \hline B5 Refurbishment & As in EN 15804+A2 & REFURBISHMENT \\ \hline B6 Operational energy use & B6, B6.1, B6.2 and B6.3, for operational energy use [6] & Not defined \\ \hline B7 Operational water use & B7, B7.1, B7.2, B7.3 B7.4, for operational water use [7] & Not defined \\ \hline Not defined in EN 15804+A2 & B8, B8.1, B8.2 and B8.3 building related users’ activity [8] & Not defined \\ \hline C1 De-construction and demolition processes & As in EN 15804+A2 & DECONSTRUCTION \\ \hline C2 Transport to waste processing facilities & As in EN 15804+A2 & Not defined \\ \hline C3 Waste processing for reuse, recovery and/or recycling & As in EN 15804+A2 & Not defined \\ \hline C4 Waste disposal & As in EN 15804+A2 & DISPOSAL \\ \hline D Potential net benefits and loads from the reuse, recycling or recovery & Divided into D1 and D2, see rows below & \\ \hline Not defined in EN 15804+A2 & D1.1, D1.2, D1.3 and D1.4 for the reuse, recycle or recovery of secondary flows [9] & Not defined \\ \hline Not defined in EN 15804+A2 & D2 Potential net benefits and loads resulting from the export of utilities such as power and heat & Not defined \\ \hline \end{tabular}
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