# Building Information Modelling Facility Management (BIM-FM)
## 8 Integrating Other Technologies  
A study by [PERSON] et al. [26] noted that it has been frequently suggested that BIM alone is not enough to meet all the requirements of FM [26] and that BIM should be integrated with the Internet of Things (IoT). However, they observed that such an integration is still in its infancy, partially due to a lack of existing studies which encourage FM to utilise IoT and a lack of interoperability between IoT technology and BIM [26]. A one way integration between IoT and BIM would constitute a Digital Shadow [93], a virtual replica of an asset informed by real-time data.  
Another potential area of integration is a Digital Twin [25]. The term 'Digital Twin' is often incorrectly used interchangeably with BIM, but the main difference is a Digital Twin is a bi-directional simulation environment where the model state changes based on external data input [94] (e.g., from a sensor) and can be used to influence the real condition. [PERSON] [94] suggested that the easiest stage to apply a Digital Twin is FM because it is much easier to track than construction. However, a current limitation of Digital Twins for BIM-FM is that static data and real-time data (dynamic) are managed differently (e.g., IFC is designed for static data only), so it is often hard to find a system that can look after both [20; 61].  
Consequently, there have been a number of attempts at sensor integration for BIM-FM with varying levels of success. [PERSON] et al. [20] attempted to use Dynamo to link the two data stores. Their work was somewhat successful but only mapped a single element at a time and contained some errors. It also was not tested by facilities' users, so it is unclear how effective it would be in practice. [PERSON] and [PERSON] [83] created a new Revit plug-in capable of integrating sensor data related to thermal comfort into Revit. The plug-in was able to visually highlight if a sensor had failed or was reporting values out of an acceptable range. [PERSON] et al. [35] proposed a system for the integration of sensors to BIM using a series of pre-existing software and BIM plug-ins. Likewise, [PERSON] et al. [95] investigated integrating sensors with BIM using three different approaches: Revit, Navisworks and Navisworks with an API add-in. They found that Navisworks was preferable to Revit as users cannot accidentally edit the model elements (but the model can still be updated within Revit and reloaded). The API add-in was the best solution as it stored historical data, hence allowing the visualisation of trends. The study by [PERSON] et al. [84] is one of the only works to successfully extend COBie to integrate dynamic data. These examples suggest that, whilst not an automatic function, sensor integration with BIM is feasible with minor development.  
[PERSON] et al. [35] do acknowledge that there are some issues with regards to installing sensors in historically significant structures. Furthermore, [PERSON] et al. [79] claim that real-time occupancy feedback is as important as sensor data as some comfort requirements cannot be measured by a sensor (e.g., how comfortable furniture is). It can be concluded that while the integration of Digital Twin/Shadow technology with BIM is feasible for BIM-FM, it should not be limited to sensor data alone, which would risk limiting its worth.