The Federated Model is the preferred model in the US and is the easiest of the workflows to implement. This is partly due to the use of viewers, which allow the use of best-of-breed applications for different parts of the BIM Model and reduce the issues associated with file size management.
The use of the Federated Model allows specialist subcontractors to use their current 3D CAD packages to coordinate and fabricate their installations. BIM-MEPAUS is working towards the implementation of the BIM-all-the-way workflow as the preferred industry workflow. The use of Federated Models is incorporated within the scheme as a transition workflow to allow the development of BIM-all-the-way without impacting on current project work in progress.