subject: What is BIM and 3D, 4D and 5D ? [print this page] Building Information Modeling is the process of converting the CAD drawings into a 3D model on the computer. The structural, architectural and mep drawings are used as inputs to create an very accurate 3D model.
Archicad and Revit are the most popular softwares used for BIM modeling.
This model can be used for:
1. For spatial visualization of the building and doing walk-throughs
2. For doing constructiblity analysis and finding discrepanices in drawings submitted by various consultants.
eg if the slab level shown in architecural drawings and structural drawings are different or if a pipe if going through a lift shaft or is there enough clear spaceinbasement rampthen BIM would be able to identify that.
3. For generating sections from anywhere in the building. Time is saved as the BIM software does this automatically.
4. Preparing Bill of Quantities from the BIM model is fast. Take-off sheets can also be prepared. This is infact called the 4D or the cost. Currently its not possible to prepare an accurate BBS from the model though Revit is making efforts towards that end.
5. The items in the Bill of Quantities can be exported to a scheduling software such as Primavera, MS Project or Vico Control to sequence the construction activities. The tasks have location data and quantity data already built into them, so scheduling is faster and more accurate. This is called 5D.
