Additional Revit modeling considerations
In my previous Revit Modeling tips for FM I covered several specific Revit capabilities and features to help you build basic models that can use successfully for facilities management. This included tips for creating facility area plans, type vs. instance parameters and how much data you should be tracking in your model to keep it meaningful and maintainable thoroughly the potentially long operational life of a facility from acquisition, through operations and finally ending with disposition. In my last post in this 5 part series I’m going to focus on some bigger picture considerations that should be taken into account when creating BIM for FM models that I haven’t covered previously.
The majority of the Revit modeling standards that have been developed for building owners have been primarily focused on documenting the attribution of the as-built conditions of a building once a building has been completed. This in a sense helps to create an accurate digital turnover for the building owner. FM:Systems has been working on modeling guidelines for building owners focused on building operations over the past years and a few of the additional considerations that we are looking at to help building owners determine what to model and to what level of detail are as follows:
What is the primary purpose of the modeled element?
Typical considerations when answering this question could include whether or not the object I am creating in Revit is being created primarily to help me run a more effective maintenance program for a particular facility or am I modeling simply for reporting/inventory purposes or perhaps a combination of both. I believe this is important for owners to consider because it gives the modeler an additional point to address when determining which attributes to track. If I have 9,000 chairs of the same type it’s probably not important to track serial numbers for instance but I might want to track an asset tag or barcode so I can keep an accurate count as part of my furniture inventory. On the other hand if I am tracking a critical mechanical asset such as a chiller I might not need to only track the originally installed serial number but also additional information such as warranty expirations, power requirements etc. as these items would be critical to maintaining this piece of equipment.
Is the modeled element fixed or movable?
If a piece of equipment is in a system and unlikely to be easily moved we most likely consider tracking several ways that this item is being hosted. For instance a chiller which probably will never move once it has been installed could be hosted not only in a room but also will be hosted as part of the mechanical system. A chair which is on wheels and moves around as-needed probably doesn’t need this level of consideration.
Spatial location and coordinate system
This point focuses more on model management and is one of the lessons I’ve learned recently; and highlights the importance of managing modeling coordinates as part of an organizations overall Revit modeling management process. This is especially important if I am bringing AutoCAD backgrounds into my Revit model from other disciplines or trades. This also applies to bringing in Revit models from other disciplines. Careful consideration of this needs to occur as part of an overall model management process to ensure that models and drawings that are used either as overlays or attachments. All discipline or trade specific models or AutoCAD backgrounds should share a common coordinate system to enable them to be referenced into each other without modification which ensures that fit together perfectly. Even being slightly off and cause huge problems and methods should be adopted by modelers to ensure accuracy.