I like to think of Virtual Design & Construction (VDC) as a process that ideally flows through a project, digitally (i.e., virtually) creating, collecting, transporting, and delivering project data from design through construction. The VDC process includes software, hardware, and people – ideally all in the proper configurations and locations to allow for cooperative participation, and enabled to deliver a high performing (i.e., optimized) constructed facility. In this context you could say that if BIM is the car then VDC is the driver. While there are a multitude of toolsets and techniques used, in my opinion there are essentially four “foundational” principles that provide a set of basic requirements for a well-designed and well executed VDC-enabled project. Simply put, these are as follows –

1. Flow of information – data must flow continuously and non-selectively between project phases and users.

2. Measurement/Control – data must be traceable and easily controlled, and allow for performance metrics to be measured.

3. Impact on Construction – VDC should drive a construction process that meets schedule, reduces cost, increases quality and minimizes risk.

4. Accessibility – VDC should enable data to be accessed by everyone involved in the project (designers, planners, buyers, managers, builders, etc.) at the point of use and in the format required.

In this context, 4D planning is arguably the most critical aspect of VDC, in that it purposefully ties the schedule progress to the design/build progress, thus enabling a timely, accurate, and useful construction plan. In order to align with the above VDC principles and fulfill the requirements for successful implementation, the 4D approach should align with an equally important set of basic principles, which I would suggest are as follows -

1. Integration – the 4D toolset must enable and sustain direct and easy import of schedule and design data.

2. Validation – the 4D data must continuously re-baseline the schedule and ensure it meets the requirements of construction

3. Optimization – the 4D data must directly contribute to faster and safer building of the project

4. Communication – the 4D data must be delivered to the field and used productively by managers, superintendents, foremen, and crew.

Most of these points are very straightforward, and may at first appear to be obvious and overly simplified, and thus not worth considering particularly in the context of a complex BIM execution plan. However, I would offer a differing view, and (along with many others) can point to under-performing VDC project efforts as being attributed to “non-compliance” with one or more of these principles. In summary, I can envision a very simple checklist based on these principles that forms a short set of key requirements reviewed by all stakeholders at the start of every project, as a key step in the project mobilization and setup process.