Clash Detection and The Wrong BIM Workflow Part II: Asia Case Study

BIM can be a way to fix problems or avoid them from the beginning

Some time ago we published an article about the main concerns that professionals from the AEC environment rise when contemplating if they should move to BIM or not. Most of those concerns have their origin in the wrong understanding of the BIM concept itself. This misunderstanding makes hard for professionals to truly see the benefits of a more smart workflow.
In the past article we explained how offices often implement BIM in a wrong way so at the end it makes them spend twice amount of their time in achieve their deliverables and end up worst than before..
Lately we have been experiencing this in first person when working as BIM Consultant for an Architecture office in Hong Kong. At the beginning we were meant to build a BIM model out of their Tender Drawings, Architecture, Structure and MEP to do Clash Detections in between these three disciplines and produce a report together with a BIM model LOD 350. This task could be much harder than it sounds..
The amount of mistakes and inconsistencies in between the “same discipline” can be huge when you work in projects in a 2D based methodology and the schedules are tight. The Clash Detection purpose is to detect clashes in between elements of different disciplines. pipes with beams, ducts with walls, or even MEP different disciplines like Drainage and HVAC in between them selves, Structure elements with finishes, etc.. Basically, to detect discordances in a project in between teams work, and with that report study the best solution for the sake of the project.

mistakes and inconsistencies in between the “same discipline” can be huge when you work in projects in a 2D based methodology


This kind of work itself makes sense to avoid these problems onsite. Makes more sense to detect all this problem on the “virtual building” than in reality when delays and errors cost much more time and money. It is a way of optimizing resources.
The main issue is that the necessity of doing this kind of work highlights a bigger problem: to start doing a BIM model after producing all 2D documentation, with all the mistakes that it involves, to fix those mistakes. Just when you read it sounds weird, right?  This is already the wrong BIM workflow, but with at least the intention of doing things right.
But if it were the end of the story it would be fine. The client gets a beautiful model that shows a lot of problems and every one work together to fix them and ease the construction of the project making the building much more accurate and efficient. The big problem comes when the documentation of each separate discipline itself is full of inconsistencies. How can you build a Model when the Floor plan and elevations don’t match? Which drawing should you follow? What if the details are different from the Floor plans, Sections and Elevations. Or you just have an elevation of a curved wall with out dimensions on it? How this would affect the works on real site?
At the end the whole process is a continuous and painful research of answers and accurate solutions. To be able to make the Model we at the end have to end up fixing the design so there is a chance to actually build the Model. So basically as BIM consultant and as Architect that want to improve the development of a project you end up doing a work that you were not supposed to be done. Although is a good feeling when some how you get to have a positive contribution on a project that may end up changing some ones mindset towards a more smart workflow.