The BIM vendor’s internal process for establishing BIM models involves creating a detailed BIM process diagram. This includes the BIM modeling workflow, illustration verification, design drawing updates, conflict review, owner review, and coordination of owner feedback. Below is a comprehensive explanation of the BIM implementation and application process, using Revit software as an example.
1. Develop a BIM Execution Plan
Before drafting the BIM Execution Plan, the BIM vendor must have thorough discussions with the project owner regarding the BIM model’s application requirements, the completion status of CAD design drawings, and the potential for future design modifications. The standard BIM proposal generally covers elements such as LOD (Level of Development), scope of work, project timeline, personnel assignments, naming conventions, project units, Revit version, and overall project scope. However, LOD alone may not fully capture the owner’s expectations regarding model detail. It is recommended to define the degree of development and functional capabilities for each component or discipline, enabling the owner to effectively approve the execution plan.
2. Set Up Basic Project Information in Revit
Based on contract and project specifications, input essential project details such as project units, project name, axis settings, project dimensions, and naming examples into Revit. Then, generate a project-specific Revit template file.
3. Determine Personnel Assignments
Once the owner approves the BIM execution plan, the BIM vendor sets up Revit model files and relevant project data according to the plan, saving these as template files. CAD drawings are imported into Revit model files according to their discipline, creating separate Revit files for each specialty. BIM modelers then begin model development based on assigned tasks from the BIM manager. Before starting, modelers should thoroughly review the BIM execution plan, modeling standards, and specific modeling requirements.
4. Verify the Latest Drawing Versions
In ongoing construction projects, design work for unfinished parts may continue while construction is underway. Completed designs are also subject to ongoing review and refinement. As the BIM model evolves, design changes may occur. Confirming the most current design drawings minimizes revisions to the BIM model later, reducing wasted effort. If there is any uncertainty about the drawing version, the design team must provide clarifications.
5. Separate Drawings by Discipline
Since CAD drawing practices vary among designers, it is necessary to split CAD drawings appropriately for compatibility with Revit. These segmented drawings are then inserted into Revit template files.
Related article recommendation: Steps for Building BIM Models
6. Build the BIM Model
BIM modelers create the model using CAD drawings, BIM execution plans, and Revit templates, completing the model development and generating Revit files for each specialty.
7. Perform Independent Quality Checks Using a Self-Inspection Checklist
The BIM supervisor conducts quality inspections of the model. Currently, internal inspection standards vary by BIM vendor, and there is no unified standard for owners to assess BIM model quality. Existing self-inspection checklists often lack detail and do not confirm adherence to specific standards. Verification largely depends on the inspector’s experience and judgment.
8. Address Model Issues
Model corrections are made based on issues identified during quality checks. If the model contains internal errors, corrections are handled within the BIM vendor team. However, if design errors are discovered, the design team must revise the drawings externally before the BIM vendor updates the model accordingly. After revisions, individual discipline models are integrated into a combined model for clash detection and resolution. Any new conflicts found after updates are rechecked. Once the integrated model passes clash detection, it is submitted to the owner for review.
If clarification is needed during drawing review, the relevant objects are marked and saved in a dedicated view, and a clarification sheet is prepared. This sheet is presented to the design team during coordination meetings, and BIM modelers proceed only after receiving revised drawings. Throughout project execution, clarification requests may be issued to the design team to support BIM model development.
The owner reviews the BIM models for compliance with contract requirements, modeling techniques, scope and content, naming conventions, information integration, and unresolved conflicts. If the owner rejects the model, they provide feedback for revisions. Due to current limitations in BIM software, some owner requests may be difficult to fulfill or require excessive resources. For example, resolving conflicts involving painted surfaces can be resource-intensive and may not significantly impact construction outcomes.
Therefore, the BIM vendor revises the model based on owner feedback and communicates any software limitations that affect correction efforts. Ultimately, model corrections should focus on fulfilling the intended BIM usage and avoid unnecessary adjustments.
That concludes our overview of the BIM implementation and application process, using Revit as an example. We hope this article provides useful insights for your BIM projects!
Must log in before commenting!
Sign Up