What Is Building Information Modeling?
September 20, 2010 — Building information modeling (BIM) has recently become a valuable technology in the facilities industry. BIM is a building design and documentation process solely based around high quality data that allows design and construction teams to generate and manage information about the project, across its entire scope. Increasingly popular, BIM is changing the process, product and delivery requirements of the facilities industry.
Traditionally, the design process was made up of manually
created, two-dimensional drawings. This has evolved into the use of
computer aided design based software, which automated this procedure.
BIM is a completely different method. Using the traditional route means
handling several 2D drafts of the projects, while BIM allows designers
and contractors to work with a single 3D model. This model handles all
of the tasks the 2D drafts are required to do, plus numerous other
assignments. The idea of the BIM model is to allow professionals to
explore a project’s key physical and functional characteristics
digitally, before it is built, and be able to interact with it during
the entire building process.
BIM is not just a 3D model - it is a process of carrying out a design, from the original design development, to the actual construction of the project. Every bit of information gathered from start to finish is placed in the model. This means that all of the design data from structural, mechanical, civil, electrical and architectural engineers are entered into the same model in which the financial, planning and legal information is stored. This way, everyone who has access to the model can locate any category of data that they desire. The way this information is stored is key to the success of BIM. With the traditional 2D CAD based process, designers produce the construction drawings. These 2D documents are then handed to the contractors through which bidding, estimating, detailing and the actual construction phase take place. With BIM, the designers and contractors can work together through the model to increase the efficiency of the project by eliminating interferences and decreasing change during construction. Construction detailing informs the design rather than following it, allowing issues to be addressed earlier, which improves the quality of the project and lowers its costs. For this to be possible, a design/build contract format would be required. A key point in BIM is interoperability. Communication between each discipline is the only way BIM can be used successfully. The construction drawings, environmental conditions, procurement details and submittal processes make up BIM’s fine details. If fully utilized, BIM provides the opportunity to prevent any information loss between the design team, construction team and owner. Each group has the luxury of referring back to the information in the BIM model.
With BIM, the pros certainly outweigh the cons. Though you will not have immediate results, once your BIM process gets up to speed, it is proven to increase your productivity. Sometimes change can be difficult, and because BIM is fairly new, it will take time to realize its advantages. Let’s take a look at some of its strong points.
Advantages of BIM
- BIM allows for more flexibility from the design of the project to the actual construction. It enables designers, contractors and owners to work through the model together to implement changes easily and efficiently.
- Changes are made easy in each phase of the model with BIM. Instead of going back to the drawing board, you simply change it in one place and the changes flow through all of the affected details. When you alter a dimension or property of a component, it is recognized by the model, and it modifies every database that deals with that element. This helps avoid any conflicts down the road that would normally slow the building process.
- The model has the technology to produce several user-friendly documents needed during the course of a project. A typical design project ($10 million or more) can contain over 50,000 pages of documents. With BIM, all you have is the model, from which any one of these documents can be produced. This feature can eliminate field or shop drawings by having parties work within the shared model. Two-dimensional and 3D PDF files can also be generated to give the owner or employees better visualizations of the design process.
- BIM offers the ability of specialized analysis tools to extract data from the design process to perform valuable analysis. Different fields of work (i.e. architects, transportation engineers, environmental engineers, etc.) use this capability for different tasks. Any category of data needed can be obtained from the work done in a BIM process. Every field has the ability to speak the same language regarding the model, from the lead architect in the design even to the project’s insurer.
Disadvantages of BIM
• Errors in accuracy - since the model is the core of the project, just one error in precision can be very costly. With today’s project method, there are several different sets of plans that can be used to check one another and prevent such mistakes. With BIM, the plans are generated from the model, so they all reflect the same data, making it harder to catch small miscalculations that can lead to bigger problems.
• BIM technologies, such as training, software costs and required hardware upgrades, are costly and it takes a lot of time to implement them into an existing process. Adequate training is needed in different areas, and levels of expertise can vary. The problem here is that because such a large amount of data is exchanged among team members, there is the risk that any weak link in the group could endanger the entire project. Also, staff buy-in is crucial to the success of BIM.
BIM is a growing technology. Though it has its disadvantages, one positive fact to focus on is the future. BIM has the potential to become the leading technology of the building industry, and it is in the interest of most firms to begin their conversion toward its processes. The more BIM is used, and the more data collected and stored during the life of a project, the more benefits can be leveraged. As users gain proficiency with BIM, they will increasingly benefit from the technology’s potential and push for new ways to gain advantages in every area of the project.