BIM execution planning and common data environments

A model produced without a plan tends to be either too thin to use or too detailed to afford. Two documents prevent this. The owner's information requirements say what information the owner needs, when and why. The BIM execution plan (BEP) is the delivery team's response: how it will produce, exchange, check and deliver that information. The common data environment (CDE) is where the information lives while it is produced. CON-120 introduced the CDE and BEP briefly. This lesson works through them in detail, using the ISO 19650 framework and the North American documents that sit alongside it.

ISO 19650 in brief

ISO 19650 is a series of international standards on organizing and digitizing information about buildings and civil engineering works using BIM. Part 1 sets out concepts and principles; Part 2 covers the delivery phase (design and construction); Part 3 covers the operational phase; Part 4 covers information exchange; Part 5 covers security-minded information management; and Part 6, published in 2025, covers health and safety information. The series uses its own vocabulary, which is worth learning because it is increasingly written into contracts.

In the United States, ISO 19650 is used by some owners and by many international firms, while others rely on the National BIM Standard–United States (NBIMS-US), maintained by the National Institute of Building Sciences. NBIMS-US version 4 is modular, with Project BIM Requirements, Project BIM Execution Planning, BIM Use Definitions and COBie modules. Federal owners such as the General Services Administration and the U.S. Army Corps of Engineers publish their own BIM guides and contract requirements, and many states, universities and health-care systems do the same, so the requirements on each project must be read carefully.

Owner information requirements

Good owner requirements start from decisions and operations, not from software. A hospital owner might need room data to check clinical adjacencies at design stage, equipment data to plan maintenance staffing, and space data to allocate costs to departments. A school board might need little more than accurate floor plans and a list of maintainable equipment. The requirements should state the purpose, the information needed for each purpose, the format, the milestone at which it is needed, and how it will be checked.

Weak requirements are common: "The contractor shall provide a BIM model at LOD 500 in native and IFC format." This says nothing about which elements, which properties, which purposes or how acceptance will be judged, and LOD 500 is not even a level of detail (Lesson 2). A construction manager who receives such a requirement should raise questions during bidding, because the cost of meeting it could range from trivial to very large.

The BIM execution plan

The BIM execution plan is the delivery team's plan for meeting the requirements. A pre-appointment BEP is submitted with a proposal to show capability; a post-appointment BEP is developed in detail after award and maintained during the project. A typical BEP covers the following.

• Project information, goals and the BIM uses chosen, with the reason for each.
• Roles and responsibilities: BIM manager, coordinators, model authors for each discipline and trade.
• Model element table (LOD or level of information need by element and milestone, with authors).
• Software, versions and exchange formats, including IFC version and property sets.
• Coordinate system, origin, units, levels and grids, tied to site control.
• CDE structure, naming conventions, status codes and approval workflow.
• Coordination process: frequency, clash tolerances, meetings and issue tracking.
• Quality checks before each exchange and at each milestone.
• Deliverables and handover, including record models and asset data.
• Security requirements, access control and confidentiality.

The BEP must be realistic. A plan that promises weekly federated clash detection with eight trades, but has no coordinator budgeted and no trades contracted to model, is not a plan. The construction manager should check that every BIM use in the BEP has a named person, time in the schedule and money in the budget.

The common data environment

A common data environment is the agreed source of information for a project, used to collect, manage and share information through a managed process. It is usually a cloud platform, but the CDE is defined by its process and rules rather than by the software. ISO 19650 describes information containers (any named file or set of information, such as a model, drawing, schedule or report) moving through four states.

Each container carries metadata: a status code (indicating what it may be used for, such as coordination, information, construction or as-built) and a revision code. A drawing shared for coordination must not be used for construction. A clear status code prevents the classic mistake of a trade building from a superseded or unapproved drawing.

Naming conventions

Consistent file and container naming lets people find information and lets software sort and filter it. ISO 19650-2 and its national annexes describe a name built from fields separated by hyphens: project, originator, functional breakdown or volume, spatial breakdown or level, information type, role (discipline) and a number. Many North American owners have their own conventions, such as the PSPC National CADD Standard in Canada or agency CAD and BIM standards in the United States. Whatever the convention, it must be written down, applied from the start and checked automatically where possible.

The master information delivery plan

The master information delivery plan (MIDP) lists every information container the delivery team will produce, with its author, the milestone it supports, its expected status and its due date. Task teams prepare task information delivery plans (TIDPs) that roll up into the MIDP. In North American practice the same function is often served by a model and deliverable schedule linked to the project schedule. The point is that information delivery is scheduled work, just like concrete pours, and should be tracked the same way.

Roles in information management

Titles vary, but the functions are consistent. The owner may appoint an information manager or BIM manager to write requirements and review deliverables. The lead appointed party (often the general contractor or design-builder during construction) appoints a BIM manager responsible for the BEP, the CDE and quality. Each task team has a coordinator or lead modeler. On larger projects, a dedicated BIM coordinator runs clash detection and coordination meetings (Lesson 5). These roles are budgeted and staffed like any other project role; if nobody owns information management, it will not happen.

ISO 19650-5 adds a security dimension: owners of sensitive assets, such as hospitals, prisons, utilities and defense facilities, should assess what information could be harmful if disclosed and set rules for who can access it. Lesson 11 returns to security.