BIM: More Than Just an Extension of 3D CAD

In the AEC industry, the advent of building information modelling (BIM) concept was viewed by many as an evolution to better 2D and 3D computer-aided design (CAD) techniques. Very few saw it as an interdisciplinary, collaborative tool that would drastically change the design-build project workflow, the management structure of AEC firms, the teaming models, the delivery standards, and the role of key disciplines involved.

As opposed to the vertical communication channels and delivery methods required by the traditional design-build approaches which mainly employ CAD, BIM necessitates an open and integrated horizontal collaboration channel between all the key stakeholders of the project: facility owners, designers/architects, MEP (M&E) engineers, consultants and contractors. To realise the benefits of employing BIM as compared to 3D CAD modelling tools, firms need to significantly invest in knowledge/skills development, personnel training, management restructuring, and software tools. However, more than these tangible investments, AEC companies need a complete change in mind set in case they want to adopt BIM for their projects.

Whilst many professionals, especially those from small and medium-sized firms, see it as an extension of 3D CAD, BIM is anything but 3D CAD. It is a much larger concept which involves extensive pre-construction planning and multidisciplinary coordination to virtually model building facilities using smart parametric objects embedded with rich accurate information. This intelligent model then can be used by all stakeholders to extract respective views and relevant information thereby resulting in timely decision-making and project delivery.

Though BIM and 3D CAD are not mutually exclusive to each other, they have major differences as far as the approach and the output is concerned. In traditional 3D CAD, depending on the scope of project, architects prepare a set of construction drawings, including the plans, sections, and elevations. Since all these views are independent entities, any change in one view has to be manually updated in others. As a result, the process is not only time-consuming but also increases the scope for errors.

On the contrary, a building information model contains the architectural, structural and MEP system models of the proposed facility. It is prepared during the design and planning stage using details from all the key stakeholders including designers, engineers, MEP contractors, and subcontractors. Since a single database-driven model represents details required by all disciplines, any changes made by any of the team members are automatically updated across the model to plans, sections and elevations. Hence, all the project team members are updated on all the changes made by others thereby saving time, reducing cost resulting from duplication of efforts, and increasing the overall quality of construction drawing sets. Thus, making small changes to the architectural plan would result in those changes appearing simultaneously in the section, elevation or schedule.

Furthermore, the building blocks of 3D CAD models are lines, circles, arcs, and other graphical entities, which lack the flexibility of data analysis. These models only serve as geometric objects devoid of detailed parameters which are required by the entire AEC supply chain. In contrast, BIM models comprise building elements and intelligent systems, including columns, beams, and walls, which contain rich data related to parameters. If needed, additional parameters can be added to the pre-existing ones for more detail. And, this rich data can be effectively shared across disciplines for rich collaboration and on-time delivery.

Nevertheless, the success of any project which employs BIM depends mainly on factors which include the richness of information embedded in the 3D models, the degree of openness in the interdisciplinary data-sharing and collaboration standards, and the level of mutual trust among all the professionals involved. If prudently planned and implemented, a BIM model not only represents the essential building elements in detail; valuable information concerning spatial coordination, geographic location, quantity take-offs, material requirements, time schedule, and project cost can be extracted when needed.

In essence, a well-planned BIM model accurately represents the entire project design lifecycle. Though preparing for and implementing BIM strategies requires considerable investment of time, money, and effort, its benefits are multi-faceted and long-term.

As a result, if your firm operates in the AEC industry and is looking for an outsourcing vendor offering a cost-effective, high-quality BIM modelling and CAD drafting services, kindly contact us.

Approaching MEP BIM Projects Using Coordination Specialists

The MEP (M&E) design and contracting industry across the globe faces renewed challenges with the advent of BIM which is increasingly used by AEC firms. Firstly, of all the major stakeholders involved in an AEC project, building systems design and engineering historically formed the last phase of design, however BIM dictates a more synchronised approach by all disciplines, requiring them to work in parallel from the early stages of AEC design. Secondly, the facility owners and investors always demand increased efficiency, waste reduction and on-time/in-budget completion.

As a result, progressive MEP engineering firms are increasingly adopting MEP (M&E) BIM practices to, a) work in parallel with other disciplines; and, b) meet complex project demands from project stakeholders.

Implementing BIM can pose a challenge as its adoption requires significant investment in equipment and training as well as changes to overall workflow and internal processes. With this in mind, many MEP engineering firm’s partner with 3D BIM modelling and building services coordination specialists, such firms possess expertise of parametric modelling and BIM development. As well as immediate expertise offered by such coordination support firms, transitioning to a BIM-based MEP workflow from a conventional CAD-based design workflow requires the type of planning and workflow streamlining that many firms are only just implementing and therefore the skills to handle such projects immediately are not in place.

Once the specialist MEP coordination firms are on board, they face the challenge of handling BIM projects and in particular maintaining a version controlled model. When using BIM for pre-construction planning and construction documentation effective communication and the use of modern collaboration platforms, usually hosted in the cloud, help to maintain a version controlled model. 

The BIM managers representing key project teams: architectural, structural, and MEP (M&E) engineering must collaborate and communicate to ensure the integrity of design data as well as adherence to project deliverables. For his/her part, the MEP (M&E) BIM manager will need to gain an insight into the architectural and structural BIM models prepared by the respective teams and use that data for his own inputs. As well as a detailed review of the current BIM standards of the project, knowing the specific components that will be used and then planning the coordination efficiently to include bracketing, lagging, access and maintenance will be taken into account. This insight can then be used to prepare an MEP central file that serves as a reference point to the downstream MEP design team.

The emerging standard of LOD (level of detail) means that the BIM manager representing the MEP (M&P) team must work to the specified LOD for the project, this will influence the detail within the drawings whether it is at the schematic design (SD), detailed design (DD) and then  construction documentation (CD) phase of the project. This ensures the model does not contain elements that are not required or will not be of any use to the trade subcontractors. Another key decision before the MEP design team starts modeling is how much custom content (parametric families) will need to be created within the BIM application in addition to the information that will need to be developed in a CAD package and linked to the BIM application.

If the above aspects are considered before initiating upon a new BIM-enabled MEP (M&E) design project, the MEP (M&E) BIM manager will serve as a primary link between the in-house design team and the architectural / structural BIM managers (who represent their respective teams). As a result, any update on the architectural or structural models will be communicated to the MEP BIM manager who can then update the MEP central file which in turn acts a point of reference for the downstream MEP design team to model upon. This sets the stage for streamlined and coordinated MEP designs using smart parametric models.

 

For more information about our dedicated MEP (M&E) BIM modelling support and coordination service for MEP (M&P) designers, consultants and contractors contact us.