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As architects or designers, we have accepted the challenge of changing our methodology to adapt to the nuances of documentation through modeling rather than drafting. We are now confronted with identifying the next step. Some firms look to create even better documents, whereas others are leveraging BIM in building analysis and simulation. As we continue to be successful in visualization and documentation, industry leaders are looking to push BIM to the next level. Many of these possibilities represent new workflows and potential changes in our culture or habits, which require you to ask a critical question: What kind of firm do you want, and how do you plan to use BIM?

As the technology behind BIM continues to grow, so does the potential. A host of things are now possible using a building information model; in fact, that list continues to expand year after year. Figure 1.3 shows some of the potential opportunities.

Figure 1.3 Service opportunities that BIM supports

We encourage you to explore ongoing research being conducted at Penn State University (http://bim.psu.edu), where students and faculty have developed a catalog of BIM uses and project implementation guidelines that have been adopted into the National BIM Standard-United States, version 2 (http://nationalbimstandard.org). Another important aspect of supporting numerous BIM uses is the development of open standards. The organization known as buildingSMART International (www.buildingsmart.org) provides a global platform for the development of such standards. Groups from a number of regional chapters around the world are generating information exchange standards that will soon have a profound impact on the ways in which we share model data with our clients and partners. Some of the latest developments are:

● IFC (Industry Foundation Classes) version 4

● COBie – Construction–Operations Building Information Exchange

● SPie – Specifiers’ Properties Information Exchange

● BCF – BIM Collaboration Format

● UK-based BIM Task Group (www.bimtaskgroup.org)

For a general overview of the approach to standardizing exchanges with information delivery manuals (IDMs) and model view definitions (MVDs), visit www.buildingsmart-tech.org/specifications.

When moving to the next step with BIM – be that better documentation, sustainable analysis, or facility management – you should look at your priorities through three different lenses:

● Visualize

● Analyze

● Strategize

Understanding these areas, specifically how they overlap within your firm, will help you define your implementation strategy for BIM tools and processes.

Visualizing

Creating documentation using BIM gives you the added advantage of being able to visualize the project in 3D. Although this was initially conceived as one of the “low-hanging fruits” of a BIM workflow, this benefit has led to an explosion of 3D graphics – perspectives, wire frames, cloud renderings, and animations – within the industry as a means to communicate design between stakeholders on a project.

This digital creation of the project has given us a variety of tools to communicate aspects of the project. It becomes “architecture in miniature,” and we can take the model and create a seemingly unlimited number of interior and exterior visualizations. The same model may be imported into a gaming engine for an interactive virtual experience. Clients no longer need to rely on the designer’s pre-established paths in a fly-through – they can virtually “walk” through the building at their own pace, exploring an endless variety of directions. The same model can then be turned into a physical manifestation either in part or in whole by the use of 3D printers (known as rapid prototyping), creating small models (Figure 1.4) in a fraction of the time it would take to build one by hand. Many types of visualization are currently possible with BIM.

Figure 1.4 An example of rapid prototyping using BIM data

Source: HOK

If we consider a complete spectrum of representations, from tabular data to 2D documentation and then to 3D visualization, tremendous opportunities exist to transform the notion of traditional design deliverables. Schedules give you instantaneous reports on component quantities and space usage, whereas plans, sections, and elevations afford you the flexibility to customize their display using the information embedded in the modeled elements. For example, the plan in Figure 1.5 shows how color fills can be automatically applied to illustrate space usage by department.

Figure 1.5 Even 2D views can evolve to illustrate and analyze spatial properties.

Expanding 2D documentation to include 3D imagery also gives you the ability to clearly communicate the intent of more complex designs. It may even have a positive effect on construction by transcending possible language barriers with illustrative documentation rather than cryptic details and notations. Figure 1.6 shows a basic example of a drawing sheet composed of both 2D and 3D views generated directly from the project model.

Figure 1.6 Construction documentation can begin to transform from 2D to 3D.

Source: HOK

The obvious benefit to creating a complete digital model of your building project is the ability to generate a wide variety of 3D images for presentation. These images are used to not only describe design intent but also to illustrate ideas about proportion, form, space, and functional relationships. The ease at which these kinds of views can be mass-produced makes the rendered perspective more of a commodity. In some instances, as shown in the left image of Figure 1.7, materiality may be removed to focus on the building form and element adjacencies. The same model is used again for a final photorealistic rendering, as shown in the right image of Figure 1.7.

Figure 1.7 Two different methods of using 3D presentation views

Source: HOK

By adding materiality to the BIM elements, you can begin to explore the space in color and light, creating photorealistic renderings of portions of the building design. These highly literal images convey information about both intent and content of the design. Iterations at this level are limited only by processing power. The photorealism allows for an almost lifelike exploration of color and light qualities within a built space even to the extent of allowing analytic brightness calculations to reveal the exact levels of light within a space.

The next logical step is taking these elements and adding the element of time. In Figure 1.8, you can see a still image taken from a phasing animation (commonly referred to as a 4D simulation) of a project. Not only do these simulations convey time and movement through space, but they also have the ability to demonstrate how the building will react or perform under real lighting and atmospheric conditions. All of this fosters a more complete understanding of the constructability and performance of a project before it is realized.

Figure 1.8 A still from an animation showing accurate physical conditions for the project

Source: HOK

BIM AS A SINGLE SOURCE MODEL

In the early 2000s, if you wanted to create a rendering, a physical model, a daylighting model, an energy model, and an animation, you would have had to create five separate models and use five different pieces of software. There was no ability to reuse model geometry and data between model uses. One of the key uses of BIM is the opportunity to repurpose the model for a variety of visualizations. This not only allows you to not have to re-create geometry between uses, but also ensures you’re using the most current information in each visualization because it all comes from the same source. As the capacity of cloud rendering and analysis grows, the feedback will no longer need to process locally and you’ll be able to receive feedback faster.

Analyzing

As with visualization, the authoring environment of a BIM platform isn’t necessarily the most efficient one on which to perform analysis. Although you can create some rendering and animations within Revit, a host of other applications are specifically designed to capitalize on a computer’s RAM and processing power to minimize the time it takes to create such media. Analysis is much the same way – although some basic analysis is possible using Revit, other applications are much more robust and can create more accurate results. The real value in BIM beyond design documentation is the interoperability of model geometry and metadata between applications. Consider energy modeling as an example. In Figure 1.9, we’re comparing three energy-modeling applications: A, B, and C. In the figure, the darkest blue bar reflects the time it takes to either import model geometry into the analysis package or redraw the design with the analysis package. The lighter blue bar reflects the amount of time needed to add data not within Revit, such as loads, zoning, and so on. The lightest bar represents the time it takes to perform the analysis once all the information is in place.

Figure 1.9 BIM environmental analysis time comparison

In A and B, we modeled the project in Revit but were unable to use the model geometry in the analysis package. This caused the re-creation of the design within the analysis tool and also required time to coordinate and maintain the design and its iterations between the two models. In application C, you can see we were able to import Revit model geometry directly into the analysis package, saving nearly 50 percent of the time needed to create and run the full analysis. Using this workflow, you can bring analysis to more projects, perform more iterations, or do the analysis in half the time.

The same workflow is true for daylighting (Figure 1.10) and other types of building performance analysis. With the ability to repurpose the Revit model geometry, we are able to move away from anecdotal or prescriptive design solutions and begin to rely on calculated results. Using Revit also ensures consistency because the model is the sole source for design geometry.

Figure 1.10 Daylighting overlay from Autodesk® 3ds Max® Design software

Building analysis can reach beyond just the design phase and into the whole building life cycle. Once the building has been constructed, the use of BIM doesn’t need to end. More advanced facilities management systems support tracking – and thereby trending – building use over time. By trending building use, you can begin to predict usage patterns and help anticipate future uses such as energy consumption or future expansion. This strategy can help you become more proactive with maintenance and equipment replacement because you will be able to “see” how equipment performance begins to degrade over time. Trending will also aid you in providing a more comfortable environment for building occupants by understanding historic use patterns and allowing you to keep the building tuned for optimized energy performance.

Strategizing

To maximize your investment in a BIM-based workflow, it’s necessary to apply a bit of planning. As in design, a well-planned and flexible implementation is paramount to a project’s success. By identifying goals on a project early on in the process, it allows BIM to be implemented efficiently to reach those objectives. An effective strategy answers three key questions about a project:

● What processes do we need to employ to achieve our project goals?

● Who are the key team members to implement those processes?

● How will we support the people and processes with technology or applications?

Ask these questions of your firm as a whole so you can collectively work toward expertise in a given area, be that sustainable design or construction or something else. Ask the same questions of an individual project as well so you can begin building the model in early stages for potential downstream uses. In both cases (firm-wide or project-based), processes will need to change to meet the goals you’ve established. Modeling techniques and workflows will need to be established. Analysis-based BIM requires different constraints and requirements than a model used for documentation or clash detection. If you’re taking the model into facilities management, you’ll need to add a lot of metadata about equipment but at a lower level of detail than if you were performing daylighting studies. Applying a new level of model integrity during a design phase can be a frustrating and time-consuming endeavor. Regardless of the goal, setting and understanding those goals early on in the project process is a prerequisite for success.