Contractual Standards for Enhanced Geometry Control in Model-Based Collaboration

This paper discusses the definition of contractual standards for ICT-enabled business models and value-driven business models, focusing on model-based collaboration for enhanced geometry control. While a growing number of highly publicized international complex-shaped buildings have demonstrated the usage of three-dimensional (3D) modeling as the primary means for geometric representation, the authors have observed a lack of contractual standards around the 3D model. Process complexities that are deeply embedded in practice conventions, along with legal constraints and risk allocation, pose challenges to the establishment of standard agreements. As a result, individual project teams often struggle to define and find adequate design agreements to facilitate effective control of geometry around the 3D model. Ineffective geometry control may result in schedule delays when project participants disagree on the representation of the 3D model, or even change the original design intent, eroding the integrity of the design. Thus, the proliferation of 3D tools and owner demand for complex-shaped buildings creates a great need for standard design agreements over the control of the architect's geometric 3D model, in order to define control and authority, as well as a mechanism to access and verify the validity of the 3D geometry. The study presents an in-depth review and analysis of (1) the existing body of literature on effective geometry control; (2) case study examples of geometry control as a project metric; (3) an analysis of sample contract terms and the effect on geometry control approaches; and (4) recommendations for effective geometry control contract terms, processes, and strategies for owner-architect and owner-designer standard agreements. The paper's principal value lies in (1) its definition of geometry control as a performance metric and (2) its guideline for standard contract terms to facilitate effective geometry control via design agreements. The results will complement existing industry efforts by owner organizations such as the Construction Users Roundtable and design organizations such as the American Institute of Architects.