The integrated nature of BIM allows for clear exposure of overlapping systems, or clash detection. The flip side of such clarity is ambiguity with regards to liability. How are notions of authorship and ownership redefined in a process that is by its nature collaborative?

Zetlin & de Chiara, a New York legal firm specializing in the architecture and construction industries, is attempting to address these issues. Though the examples of completed buildings designed with a BIM approach are still few, partner Michael Zetlin and his colleagues, many of whom are trained engineers and architects themselves, began to field anxieties from their clients a number of years ago. If a CAD document is transferred on a disk, the roles of the parties are still the same, and contracts have dealt with what happens if data is corrupted or drawings are altered by a specific party,, he said. But when you come to the shop drawing process [in a BIM workflow] and have a room full of people, including the steel fabricator, the mechanical engineer, and CM, all looking at a 3D model and inputting details, ownership of the design becomes blurry..

William Sharples, a partner of SHoP, believes that working closely with the other parties is in itself a proactive way to avoid conflict. Americans are litigious in general,, he said, but just working in a BIM model allows everyone to sit down and have an informed, intelligent conversation where all parties are speaking the same language. It creates an environment of trust.. As an example, Sharples cited a problem that arose in the field while his firm was building the Camera Obscura, a digitally designed and fabricated project in Greenport, Long Island. When one of the precision-cut exterior wood slats did not fit in place, he said there was no difficulty in tracing through the model where the problem began, and the situation was resolved with relative ease between the architect, fabricator, and construction team.

There is yet to be a legal precedent for BIM-developed buildings and Zetlin believes that, for a while, cases will be decided on a project-by-project basis. But he is certain that working together in such a different way calls for modified contractual language. Sit down with the owners and determine, for example, who will be the keeper of the model, or whether or not the steel engineer will be accountable for a specific detail determined in shop drawings,, he advised. Think through very carefully at the beginning how responsibility will be allocated among the project team..

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