Clash detection is seen as one of the great benefits of the BIM Level 2 process. As the individual author models are federated, clashes can be identified. The authors of the native models and the lead designer can discuss how the clash is best resolved and an instruction issued to the author of the model that is to change.
The clash detection process involves collaboration and the management of that process. The CIC protocol assumes that someone other than the BIM manager will be responsible.
The industry has not yet produced a standard solution for managing this. Where design is developed by a single team, the information manager and lead designer roles may be established at inception and may not need to move as the design is developed. In a design and build structure, where responsibility for developing the design moves from an employer to a contractor, it is likely that either or both roles may need to transfer, as design responsibility, model delivery and production moves from the client team to the contractor.
In this web of liabilities and obligations it is important to provide a consistent structure. Our industry building blocks of consultant appointment documents and standard building contracts do not produce that consistency when delivering BIM. In many respects, such documents do not even deal with the issues we need to address to achieve satisfactory BIM collaboration.
For example, rights to access and use data in a common data environment are not part of our standard documents, and copyright solutions may not be adequate to allow the collaboration the team needs.
Further, BIM objects and their associated intellectual property may be produced or owned by third-party libraries or manufacturers, and provided on terms that may be inconsistent with traditional documentation. Software licensing, too, is not usually part of the standard contract.
However, the complexity of collaboration is recognised in certain procurement models and standard documents. One solution is a multi-party contract, such as PPC2000. This can provide a template of solutions for the whole team.
Providing the template for how parties are to contract is one thing, but monitoring what they do in practice and helping them to get it right is also an important role. PPC2000 provides for a “partnering adviser” to help the parties complete and document the collaboration. If we are to produce documentation that is “clash free”, perhaps we need to consider the same for BIM.
Whether we adopt a multi-party solution or remain with a bilateral contract structure, there is a need for someone to take responsibility for ensuring that documents are fit for their purpose, and that parties complete the documentation so that it is clash free.
By Tim Willis, a consultant in Trowers & Hamlins’ dispute resolution and litigation department
Main image: At HMP Oakwood Prison, Featherstone, clash detection exercises were carried out in Navisworks and used throughout construction to demonstrate to the MoJ’s technical advisers, and Faithful + Gould’s project management team, that the scheme was being delivered in line with the design.