In defining the different maturity levels of BIM, the concepts of 4D, 5D and 6D are used to indicate the elements and benefits of increasingly complex BIM models.
There is a wide spectrum of possible uses of BIM on construction projects. At one extreme architects and engineers can use BIM simply to produce better quality design documents without providing the digital model to any other party. Contractors, likewise, can separately create models for estimating, fabricating or simulating construction without sharing the models.
Used in such limited ways, BIM does not come close to realising its full potential. At the other end of the spectrum, BIM can provide a collaborative framework among all project parties, allowing the free-flow of data about what is being designed and how it will be constructed. Collaborative use of BIM takes full advantage of BIM's capabilities.
3D – Model * Model walkthroughs. These provide a great visualisation tool enabling designers and contractors to work together to identify and resolve problems with the help of the model before walking on-site. * Clash detection. Traditionally design drawings must be coordinated to assure that different building systems do not clash and can actually be constructed in the allowed space. Accordingly, most clashes are identified when the contractor receives the design