Application of BIM and GIS in Class 1-5 Cost Estimates

Application of BIM and GIS in Class 1-5 Cost Estimates, Apostolos Chatzisymeon PE; Nick Papadopoulos; George Chatzisymeon, 2012 AACE International Transactions, BIM.846, AACE International, Morgantown, WV, 2012

Building Information Modeling (BIM) and Geographic Information Systems (GIS), based on open standards, transform the way the cost engineering industry works and will work in the future. This paper presents four examples to demonstrate how BIM and GIS can be applied to all classes of estimates. The first example includes a building, in conjunction with GIS, to model and optimize a real estate development project to produce a Class 5 estimate. The second example demonstrates how architectural BIM sketches can be combined with smart assemblies that use conceptual cost data to produce a Class 4 estimate. The third example uses a basic design BIM model, combined with commercial assemblies, to produce a Class 3 estimate. The fourth example uses a detailed Industry Foundation Class (IFC) model for a quantity takeoff, and combined with commercial databases, generates a Class 2 estimate. The same BIM model is used as a basis for creating and managing quotes from suppliers and subcontractors and developing definite Class 1 estimates. The resource and cost loaded detailed BIM model is examined through value engineering and analysis as an alternate method for presenting proposals.