Cost estimation with BIM also known as BIM 5D can be done by connecting a 3D model to an estimation database (a 5D cost library). Higher level of details can be applied to these estimates at various stages of the project.
3D models are fed with multi dimensional objects and related information about the elements of these objects - for example, the quantity and specification details.
Here, in BIM, the information about each element is associated with the corresponding geometry. Any change in the design, leads to change in geometry and hence the associated information also instantly changes (updates).
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