Goal:

Status of Use Document: Draft

Phase(s):

Design Development and Construction Documents

Objective:

[_] Designer and consultants/AE’s develop 3D models in their own disciplines with the purpose of integrating them in one model, identifying and resolving potential conflicts during design development and construction documents phase through coordination meetings and time before the construction begins and more money and time is invested
[_] The intention is to bring all the parties involved at the same table and resolve design issues and conflicts between different systems and connections before the design is handed off to contractor, subcontractors, fabricators and detailers
[_] Coordination of building model with information from various disciplines
[_] Coordination with the engineering team for control of geometry and layout

Description:

3D coordination effort starts with each of the stakeholders creating their own designs and 3D models, setting up and organizing the whole process in 3D modeling meetings which can happen weekly, bi-weekly or in any other organized manner. The parties involved in design coordination are usually: architect, consultants: structural, mechanical, electrical/lighting engineers, owner and construction manager, if decided to join the coordination process early in design. One of the first tasks to be accomplished is agreeing on the scope of work for each discipline and level of detail of building systems and components that will be required for efficient 3D design coordination and providing basic means and methods of construction to the contractor (Leicht and Messner, 2008).

The next task would be to agree on methods of sharing the model and architectural backgrounds. When the project is in the design development stage architect can share the model with the consultants so that they can start their design process. Final step would be integrating individual 3D models into one model for the purpose of interference detection and resolution. Using BIM authoring tools with clash detection capabilities or design review software intended for this purposes a standard file should be set up where each designer or consultant can upload their corresponding 3D models according to previously defined orientation and scaling. A pilot test run can be executed easily, conflicts report printed and geometric interference detection process evaluated and modified for future reference (Leicht and Messner, 2008). This pilot test run and agreement on the procedure should lead to follow up coordination meetings in the next weeks to identify, document and resolve all major issues before the construction documents are finalized and handed over to the contractor, subcontractors, fabricators and detailers for shop drawings and start of construction.

Each conflict is discussed and resolved during or right after the coordination meeting, and the process is repeated until all the involved parties believe to have achieved a 100% collision free design, and it is up to contractors and subcontractors to further detail and build the project. Unless the 3D coordination was not done in full on the design level and it is up to the general contractors and respective trades to resolve the conflicts in the 3D model, which pushes coordination to the construction phase and increases the information requests and revisions required in postponed design coordination (Leicht and Messner, 2008).

Potential Benefits:

[_] Early identification of collision between building systems and components during the design process and development
[_] Resolution of design conflicts before the design is handed over to the contractor and construction begins
[_] Improved communication and collaboration between architects and consultants and increased understanding and sharing information of building and design among different disciplines
[_] Potential savings in cost and time as a result of early 3D design coordination

Levels of Detail Considerations:

[_] Building systems and components should be modeled at minimum accurately and in enough detail to be able to run collision detection and determine hard and soft clashes: usually everything that is represented on a drawing with 1/4” scale should be in the 3D model as well.
[_] The level of information depends on the project and on the owner’s needs and requirements: more information input would lead to using the model for as-builts and for operations and maintenance purposes in the lifecycle of the building
[_] Model content needs to visually represent all the systems and have the level of detail to show the means and methods suggested and up for approval from contractor to construct the system

Team Competencies Required:

[_] Comfortable with modeling the design in BIM authoring tool and input the information
[_] Comfortable with using the design review software and leadership in implementation and execution of 3D design coordination on a project

Characteristics in order to substantiate BIM use:

Project -
Organization -
Environment -
Contract -
Process -

Potential Modeling Methods:

  • Design/Construction engineering firm develops 3D model files
  • Sub-contractors model systems in defined file formats
  • Separate 3D models are collected by engineering firm and coordinated into primary 3D building model
  • Sub-contractors have continuous access to primary 3D building model and systems can be updated in real-time

Designer is in charge of starting the 3D BIM model, and consultants or AE’s take over the model in design development stage to input their designs. Crucial is to come to understanding of the file formats being used and their compatibility and interoperability for future coordination efforts to be successful and building systems and components to be updated in real-time.

Potential Outputs:

  • 3D model can be handed over as 100% collision free to the contractor or the owner if requested.

Legal / Commitment Considerations:

  • Consider the level of coordination and the issue of what level of detail is expected in design coordination by the designer vs. the contractors.

Additional Resources:

General Description: N/A


Quantitative Studies: N/A


Case Study Examples:

  • City Hospital, Southeast Pennsylvania: BIM 3D Model Implementation Investigation (Belizaire)
  • Dickinson School of Law Building, State College, PA: “Moving Toward an ‘Intelligent’ Shop Modeling Process,” (Leicht and Messner 2008)

Software Applications:

  • NavisWorks
  • Revit
  • Sketchup
  • Solibri
  • AutoCAD
  • AutoCAD MEP
  • QuickPen
  • HydroCAD
  • Bentley Project-Wise Navigator etc

References:

Belizaire, M. “City Hospital Pennsylvania: Phase 1,” <http://www.engr.psu.edu/ae/thesis/portfolios/2008/mxb951/>, September, 2008.
Leicht R., Messner J., 2008. “Moving toward an ‘intelligent’ shop modeling process”, ITcon Vol. 13, Special Issue Case studies of BIM use, pg. 286-302, http://www.itcon.org/2008/20.