by Richard McPartland
The common data environment (CDE) is a central repository where construction project information is housed. The contents of the CDE are not limited to assets created in a ‘BIM environment’ and it will therefore include documentation, graphical model and non-graphical assets. In using a single source of information collaboration between project members should be enhanced, mistakes reduced and duplication avoided. Here we explore the CDE in more detail...
Why establish a CDE?
Many BIM protocols, in particular the CIC BIM Protocol , propose the use of a common data environment. The ultimate aim being to improve the creation, sharing and issuing of information that underpins the delivery of your project. The idea of collaboration to drive improved results and efficiencies is at the heart of implementing a Building Information Modelling (BIM) approach on construction projects.
Who contributes to the CDE?
Construction draws on the skills of a wide range of disciplines and the CDE brings together the information from all who work as part of the wider project team.
For example, a project might have inputs and deliverables from architectural, landscape, structural, civils/infrastructure and mechanical, electrical, plumbing/services staff and these will be added to the CDE as data drops at specific points in the project set out in Employer's Information Requirements.
What form does the CDE take?
It’s really up to you and your project team. PAS 1192 2 suggests you could set up a server for your project, or perhaps an extranet or some other form of file-based retrieval system.
In establishing a CDE you should be mindful of the requirements of contributing parties. File naming conventions - perhaps, using a standard protocol such as that in BS 1192:2007 , will need to be established early. So too will any information security pre-requisites - our article on Implementing a security-minded BIM approach is a good place to start.
In practice the CDE may be divided to create environments that serve the needs of those on the supply side of a project and to collate and validate the deliverables that are required for Employer's Information Requirements. These environments may have distinct permissions, structures and protocols.
What do I need to consider when working with the CDE?
The CDE itself is not a project management tool though can be used with one or many such tools.
See also: Top tools for online collaboration
In working with files collaboratively you should consider some kind of workflow / sign-off process so it is clear which information remains work in progress, which has been shared (following appropriate review) and which published (following stakeholder sign-off). You'll also need to think about versioning of assets and archive for those that have been superceded.
What advantages do I get from using a CDE?
As a single source of information there’s no arguments about which version of information should be being referenced. The CDE should serve as the ultimate source of 'truth' and bring a number of advantages for all involved:
- Shared information should result in coordinated data which will, in turn, reduce both time and cost on your project.
- Project team members can all use the CDE to generate the documents/ views they need using different combinations of the central assets, confident that they are using the latest assets (as are others).
- Spatial co-ordination is inherent in the idea of using a centralized model.
- Production information should be right first time assuming that contributors adhere to processes for sharing information.
Who is responsible for the CDE?
The CIC BIM Protocol proposes that an ‘information manager’ (as distinct from BIM co-ordinator, with no responsibility for design, clash detection or the co-ordination of models) is appointed. The information manager is responsible for keeping the myriad of information being generated and shared both synchronised and coherent. In practice a senior team member will typically take on this co-ordination role.
Who owns the information in the CDE?
The contributor retains ownership of the information they store in the CDE. Indeed, models produced by individual teams will always remain separate and it is these that are then drawn on to produce the federated model.
Typically team members will licence their contributions for use by the client for a prescribed purpose (ie. generating the federated model to the level of detail contractually set out in Employer's Information Requirements). In turn, clients can then licence the range of models fed back to the CDE for use by other members of the project team for their requirements.
Ownership may change as the project progresses and decisions are made - objects specified by the designer, for example, will be swopped out by sub-contractor(s) with particular manufacturer's objects, for example. The information manager must be mindful of these changes of status.