BIM - Project Execution Plan (PXP)

Structure of a project execution plan
One of the most widely referenced and accessible BIM planning guides and templates is theNational BIM Standard (NBIMS) Project Execution Plan v2.1, which was developed at Penn State University.2 Also referred to as the NBIMS Guide, it has been endorsed by both the Institute for BIM in Canada (IBC) and the buildingSMART Alliance (bSa).

At a generic level, the plan can be broken into three parts as shown in Figure 1:

• “Uses and Goals;”
• “Processes and Exchanges;” and
• “Supporting Infrastructure.”

NBIMS Guide takes a needs-based approach to ensure project goals and stakeholder capabilities are considered before any BIM uses are selected for the project. The team also needs to build a good understanding of the processes that will be followed to achieve the expected BIM uses by identifying tasks and the information (model) flow. Detailed reviews of the required information from models for each task follows based on use and information sources. Finally, the PxP establishes and records the technology, data, and model structure requirements, along with collaboration and quality control procedures.

Uses and goals (NBIMSGuide, Sections 1−3)
Two main elements are considered before BIM uses for a project are selected: business goals and the capabilities (sometimes anticipated) of the project participants. Even basic business goals can be contradictory (e.g. cost versus quality); these must be realistically prioritized for the project. Specific BIM uses can then be identified that support each goal’s achievement (Figure 2).

There is a tendency to be overly optimistic about what can be achieved with BIM. For this reason, analysis is necessary to assess which uses are practical and will deliver tangible benefits for the effort required. This requires considering who is involved, the value and cost of BIM to each stakeholder, and the capability of participants to deliver the resources required. Once this initial work is done, the decisions about goals and uses can be made, and the high-level BIM roles and responsibilities of the participants can be recorded.

Processes and exchanges (NBIMSGuide, Sections 4−5)
Once the project’s BIM uses are selected, the work needs to be broken into tasks and the flow of BIM information must be identified. The goal is to capture how information will be shared, which project participant will create the models (and when), and what specific information will need to be included in the models.

Describing in any detail how to create a process map is beyond this article’s scope, but the process is typically modelled at two levels. Usually a single Level 1 map is created to cover the overall main project tasks and deliverables (Figure 3). Level 2 maps are created for each task identified at Level 1 to examine the roles of individual stakeholders and flow of modelled information in that task (Figure 4).

Attention to detail here is important as these maps define the regular flow of project activities and support the later identification of information requirements—which elements and what level of development—for each model to be shared or exchanged in the project. The NBIMSGuide provides generic process maps that can be customized to particular circumstances if necessary.

Whenever one professional shares modelled information with another, there needs to be an understanding of what information is expected. The information-exchange worksheets (Figure 5) help define the information requirements of the model recipient and identify which model creators will author information elements. It is important to establish these exchanges early, before they become an issue during the project. The results of these worksheets often become an important part of the project contracts.

The information-exchange descriptions usually include specification of the level of development (LOD) definitions being used. (For more, see “Level of Development.”) They also include specific notes on what may or may not be required in the model (e.g. conduit smaller than 38 mm [1.5 in.] in diameter).

Supporting infrastructure (NBIMSGuide, Sections 6−11)
The logistics of a BIM project are typically not very glamorous or complicated, but finalizing them with the team is important for project success. The logistics convert all the decisions made in building the plan into well-defined tasks, processes, or deliverables over a significant range of fundamental operational aspects.

1. ‘Facility data requirements’ include any client-side BIM deliverable expectations, usually for facility or asset management purposes.
2. ‘Collaboration procedures’ record planned meeting strategies, exchange procedures (e.g.frequency, file format, naming, location, and servers), access rights, and related roles and responsibilities.
3. ‘Quality control (QC)’ outlines the requisite model checks, review processes and any tolerances or standards to which the models must adhere.
4. ‘Technology requirements’ cover software versions and hardware recommendations.
5. BIM models can become very large so most projects work with multiple distinct, but correlated, models according to disciplines, systems, floors, and/or zones as defined beforehand in the ‘Model Structure’ section.
6. ‘Project BIM deliverables’ simply serves to itemize the overall expected BIM-related deliverables for the project, when they are due, and their formats.