The advent of computers have brought about a revolution in the design industry. Designing on computers has changed the way that designers and architects work. With the availability of different software such as CAD and BIM software, professionals often face a dilemma while selecting the appropriate tool for the project.
- CAD software is cheaper than the software for BIM.
- The skill set required to produce CAD drawings is limited to the knowledge of 2D drafting skills. A 3D CAD model is generated by drawing lines.
- CAD is easier to work on to create a 2D drawing as all the process are direct processes. For e.g. if you need to represent a line, you just need to draw a line. In BIM, line is a product of indirect process e.g. the façade view derived from the 3D model of the window which, in turn, is an assembly of parametric 3D objects.
BIM is a model based approach to design.
- It captures reality in a way that 2D drawings are not able to capture. With the availability of various mapping tools, aerial imagery and laser scans of existing infrastructure have turned out to be the starting point of a project. This information can be integrated with the BIM model.
- It has a multidisciplinary approach to design. The design parameters from all the disciplines are assimilated in the model which results in a better coordinated design.
- It facilitates synchronization between all the drawings such as plans, elevations, sections, perspective etc. as all these drawings are extracted from the model. Any change in the design is incorporated in the model. This change is automatically updated in all the drawings that are extracted.
- Lot of labor and time is saved when deriving quantities from BIM model with the use of tools such as element counts, volumes, areas, etc.
- Simulation tools in BIM software allows designers to visualize various parameters. It also allows the designers to do much more analysis with the click of a button.
- The BIM toolset helps in resolving conflicts between elements of different disciplines that arise in the design. For e.g. it can resolve clashes that arise when an electrical conduit runs into a beam.
The various advantages that BIM offers over CAD has prompted the Industry big wigs to adopt BIM. Any human error has a probability to get carried forward in CAD but not with BIM. BIM modelling, thus, is a holistic approach to design. With the numerous benefits that BIM modelling services offer over CAD, BIM is undoubtedly an efficient and intelligent approach.