BIM – Building information modelling

Opportunities and challenges

Building work and maintenance depend on coordinated information and collaborative working. The quality and reliability of BIM has great influence on the outcome. Poor management and use of information is one of the major problems in design, building and maintenance.

Some of the greatest benefits of using BIM can be summarised as follows:

• BIM capable software automates drawing coordination between plans, sections and elevations
• It facilitates the consistency of the graphic information in the documentation
• Supports increased accuracy of documentation if modelled and checked correctly
• Provides virtual coordination capabilities and clash detection and resolution
• Conveys the design intent in a coordinated 3D environment with true dimensions
• Sketches, tests, validates and illustrates all in the same geometric environment
• Environmental and sustainable design is now working with real data and can be reliably validated
• Assists in exploring different design options
• Translates complex and seemingly random concepts into systems
• The team all work in and share the same file, ie no disconnected file management
• Enables real-time navigation and visualisation for stakeholder presentations
• Objects with embedded information supported by manufacturers increase quality of schedules
• The information in the model can be extracted to create schedules of building components, materials and quantities providing the ability to better manage the construction cost
• The virtual model can be used to rehearse the construction of the building and in return reduce wastage of time, materials and cost.

There are, however, considerations that have to be made in relation to a practice’s operation and procedures. These considerations can impact on a practice’s finances and resourcing.

Immediate challenges

• Hardware upgrades and software costs can be substantial
• Changing processes and project workflows including investing project time at the early stages in establishing the model
• Setting up the project model to align with the desired project BIM outcomes
• Establishing office standards and protocols takes considerable effort, time and engagement by everyone involved in projects including senior level staff
• Staff training required on software and process
• Time and resources to create office templates and object libraries.

In addition to the impacts mentioned above, the design workflow may have to shift dramatically. Mindsets need to be adjusted to new workflows and new technology, which necessitate a shift to more up-front efforts where resolutions are forced to be solved earlier than in traditional methods of design. Some additional considerations to be taken into account include:

• Project startup and file setup time is increased and needs additional site information
• The production of schematic drawings may take longer in order to guarantee accuracy moving on to the design development stage
• As drawings are automatically derived from the model, graphic representation may not fully align with existing office standards
• Design resolution will need to occur in the earlier stages of the design process
• A shift in resources demand to the early stages of the project, in setting up the model and working through detailing upfront, compared to traditional documentation
• Added resources to manage the models and additional data input created by new agreements.

Considerations before signing an agreement

Architects should ensure that the following issues are clarified with the client before committing to delivering a project in BIM:

• What is the main purpose of the BIM model? Is it required for the purpose of extracting quantities, scheduling construction works, off-site manufacturing or facility management?
• Is there a clear project procurement plan? Will the project be delivered based on the traditional method Design-Bid-Build or is the client considering early engagement of a contractor? Will the architect be contracted to the client for the full duration of the project or will they be novated to the contractor?
• Is the client intending to nominate a subcontractor? Is the nominated subcontractor expected to take part in the design and documentation process? Are they BIM ready? Do they have any specific operational requirements that have to be taken into account during the design?
• Has the client appointed a BIM manager or are they expecting the architect to fulfill this role? If the architect is required to manage the BIM process, is their fee and resource capability adequate?

It is essential to establish what the client requirements are and how they intend to use the model. Failure to confirm this at project inception could result in significant financial losses to the architect as they may be required to undertake work that has not been anticipated and accounted for. This can create confusion and disruption for all parties through the design and documentation process and result in client dissatisfaction. Managing client expectations is critical as many do not understand the principles of BIM and tend to ask for more than they need.

Do not sign contracts with terms you don't understand. Standard BIM contracts can include unfamiliar terms such as LOD (Level of Development), Cobie, 4D, 5D, IFC, and FM. Often they are completely outside the traditional scope and professional indemnity insurance cover for architects. One of the most common mistakes architectural practices make is to sign a BIM contract containing an overarching requirement for BIM model LOD. Labelling a model by LOD devalues the usefulness of the concept. It is more accurate to define the model by its place in the design program, eg design model, record model (refer Figure 1). There is no such thing as an LOD 300/LOD 400 model. LOD is associated with building elements/objects; therefore, it cannot be assigned to the model as a whole. It must be assigned to individual objects of the model (Refer Figure 2).

The most critical document that defines the BIM deliverables is the model element matrix . It confirms the model element deliverables in terms of LOD. Architectural model and documentation standard deliverables as defined in the model element matrix do not venture beyond LOD 300 and could be even lower for specific elements such as waterproofing, coatings and supplementary components. LOD 350–400 are in the realm of shop drawings and fabrication and therefore fall outside the scope and expertise of an architectural practice.

LOD and model element matrix

The model element matrix is a document that sets the expectations for all modelled elements in the project. The original matrix was created by the United States Army Corps Engineers (USACE) to inform the design and construction team of modelling and detailing responsibilities (ie which elements must be modelled by whom, when, and to what LOD for each stage of the project). The use of a matrix based on the USACE M3 System is recommended and is also referenced in the NATSPEC paper: BIM and LOD Building Information Modelling and Level of Development, available at: bim.natspec.org/documents/natspec-national-bim-guide

Figure 1. Sample model element matrix (Image: courtesy of HASSELL)

Figure 2. Typical Level of Development (LOD) progression (Image: courtesy of HASSELL)

BIM brief and BIM management plan

A BIM brief is a high level document covering the BIM goals of the client. As clients are often not familiar with BIM, it is recommended to initiate a brief jointly with the architect in a similar way to how design briefs are developed. It is important to highlight the perceived and expected benefits of BIM by the client. The BIM brief should capture requisite BIM uses, project phases and procurement and should be expanded to cover the requirements for the client, architect, project manager, design consultants, etc.

The BIM management plan (BMP) is a formal document that defines how a project will be executed, monitored and controlled with regard to BIM. One of its main purposes is to make clear what members of the project team can expect from each other – who is meant to do what, how, and when in regards to BIM. This is an essential document on BIM related projects and is prepared on the basis of the BIM brief and in association with other contractual documents. NATSPEC BIM has produced a standard set of templates under open general license:

• Executive summary/BIM brief (a high level document covering goals)
• Design BIM Management Plan (for clients, project team leaders and model managers - those with a management focus and intermediate BIM skills during the project’s design phase)
• Technical appendix (a document containing detailed technical information).

More information can be obtained at: bim.natspec.org/documents/bim-management-plan-template

Collaboration and coordination

One of the advantages of BIM technology is that it can create a highly collaborative digital environment. It is beneficial for the project team members to use compatible modelling platforms; however, there are ways of coordinating and distributing information regardless of the platform used. There are many different software platforms that can facilitate both the collaboration and coordination process. Multi Format Viewer applications are used to aggregate/federate models from different authoring applications into one viewing platform.

The Federated model is a combined model of architectural, structural and services models. It is from this model that all automated functions like quantity measurements and clash detection are likely to happen. The federated file, once passed through the document control process, is the main reference for obtaining current information about the project by all members of the design and construction team.

Depending on the scale of the project, the Federated model can go into update cycles, resulting in potential lags in the documentation process. The responsibility for creating and maintaining the Federated model should be clear in the BIM management plan.

Legal considerations

Whatever the precise contractual application of a BIM model, it is destined to form part of the blueprint for the design of a building, therefore:

• The BIM model needs to be properly integrated into the overall project design
• Each component of the works modelled using BIM needs to be contractually specified in a way that is consistent at each level of contracting and clear to every party.

Not all of this is within the architect’s control and so has the potential to create liability issues, particularly since architects, being professional service providers have mandatory professional indemnity insurance and a higher duty of care than other consultants, if primary consultant.

To manage this risk of exposure to liability due to circumstances beyond their control, architects should:

• With the assistance of an experienced lawyer, define their contractual scope of works in a way that is clear, precise and commensurate with the degree of control that the architect has over known or foreseeable risk factors
• Involve the client and design consultants in early discussions to ensure that the client’s requirements are clearly understood
• Act at all times consistently with their obligation, when acting as primary consultant, to collaborate and coordinate the work of all consultants engaged on the project for the duration of their engagement including by warning other consultants and the client as soon as practicable of any perceived error
• Involve their insurers in contract negotiations and not be afraid to walk away from a deal with an unreasonable client
• In consultation with an experienced lawyer, consider the use of contractual caps on liability and exclusion/limitation clauses; and
• Build a risk premium into their price or fee offering where the deal involves risks outside the architect’s control.

Note: Copyright is established under the Copyright Act 1968 (Cth). Refer Acumen note Copyright and moral rights . The contract can further define obligations under copyright like 'an implied licence' or the conveying of documents in a form that can or cannot be copied.

BIM consultancy agreements

Where work is required to be undertaken by specialist consultants, the Architect-Specialist Consultant Agreement 2017 (ASCA 2017) can be used where the architect is the primary consultant and pays the specialist consultant directly.

If a BIM Management plan is in place, the architect must inform its specialist consultants on the conditions being set by the client. This will require the supplementary conditions to be referenced in the agreement.

Resources

• Building Information Modelling (BIM)
• BIM + Sustainability: Opportunities in design (Available via Online CPD)
• NATSPEC BIM
• Sustainability and Building Information Modelling (BIM)

The WA BIM working group kindly contributed to the content of this note.