BIM and Building Product Manufacturers (1-2-3 Revit Tutorial)1 Jan, 2008 By: AIA ,Rick Rundell
How building product manufacturers are providing tools and libraries to integrate their products with Revit and BIM.
For decades, building product manufacturers have had CAD-based libraries for their product lines. In turn, designers have used this content within CAD applications, primarily for the geometric data that describe the product. There has been limited use of the associated nongraphic product data associated with the building product components.
Building information modeling (BIM) and computable building information models are changing that situation as designers add more detail -- both graphic and nongraphic -- to their building information models earlier in the process to support a variety of tasks from design visualization to energy analysis and cost estimating.
This month's "1-2-3 Revit" column examines the growing trend of product manufacturers that are creating BIM-based libraries for their own product lines and looking to increase the specification of their products by enabling designers to easily incorporate their products in building information models.
The Revit building information modeling solution includes an extensive library of components. These parametric families range from basic architectural components such as walls, casework, and doors to elaborate assemblies such as kitchen cabinetry and escalators. Revit components include geometry (the component's size and shape) and design intent (how it relates to other building components) as well as nongraphic attributes that describe the component such as materials or fire rating.
Revit Architecture includes an extensive library of generic parametric components.
Because Revit components are parametric by nature, the library doesn't have to include a representation of every single size or type of component -- the library elements are preprogrammed to size accordingly. For example, six-panel colonial doors could be considered one family, although the doors that comprise that family come in different sizes and materials. When a Revit user selects a particular size and type of door, such as a wooden, 30" X 84", six-panel colonial door, the software creates a unique instance of the component, automatically adjusting the different parameter values and nongraphic properties as the element is inserted into the Revit model.
The component libraries created by Autodesk for Revit Architecture are generic. They don't describe specific manufacturer's components and therefore have no specific product information such as model number.
One of the advantages of BIM is the ability to include detailed information regarding the building even at a very early stage of the design. As such, a trend is growing toward incorporating more detailed data in the building information model, including manufacturer-specific building product data, and adding that detailed data earlier in the process.
Various motives are driving the push toward more detailed models. For example, the desire
- to better convey design ideas, even in early conceptual models
- for more accurate energy analysis and evaluations of how specific products perform in a specific design contexts
- for earlier cost estimationing information and specification applications
- to create highly detailed 3D visualizations throughout the building process.
Getting Building Component Content
As mentioned earlier, Revit Architecture includes a large library of generic components. In addition, several approaches can be used to add custom components, as well as manufacturer-specific components and related product attributes.
User generated. Revit Architecture users can create their own content using the parametric family templates that come with the software. Users also can draw on content generated by colleagues or from user community Web sites. Take note that although a lot of free content is available on the Internet, sometimes you get what you (don't) pay for and there's no guarantee that the component definition is accurate.
Commercial sites. Users also can download content from commercial sites such as BIMWorld, which develop both generic as well as manufacturer-specific BIM content. In general, downloads from these sites are free for users because the content is paid for by building product manufacturers who contract with the site to develop BIM libraries of their products.
Manufacturer sites. Content developed and distributed directly by manufacturers is the most reliable way to get manufacturer-specific product data. In fact, many manufacturers already provide (free to users) CAD representations of their products that designers can use in CAD applications. A similar trend is growing for publishing BIM representations of those products. One building component manufacturer taking the lead on this is USG.
Specify Quickly, Specify Correctly
USG Corporation is a Fortune 500 manufacturer and distributor of high-performance building systems, including wall, ceiling, flooring, and roofing products. Headquartered in Chicago, the company serves the residential and nonresidential construction markets, repair and remodel construction markets, and industrial processes. As the inventor of wallboard and mineral wool ceiling tile with flagship brands such as SHEETROCK gypsum panels and DUROCK cement board, USG is at the forefront of North America's building materials industry.
In response to the popularity of BIM, USG recently developed a Web portal -- the USG Design Studio -- an online resource for architects, designers, specifiers, and contractors to browse and select USG products and find information they need to support their role in the building process. For Revit users, the site delivers USG product content directly to the Revit platform, with design templates for Revit-specific system files that can be used for creating, defining, and manipulating interior designs. USG's Design Studio includes advanced search capabilities that aid in the identification of materials that match a designer's specific performance criteria.
USG's Design Studio enables Revit users to browse and select USG products and download those components directly into their Revit building information model.
For example, a designer can start by searching for a specific fire-rated wall such as U419 and then use other search criteria such as fire rating = 2 hours, minimum STC of 50, and systems that do not require insulation to filter down to a group of products that fit the designer's requirements. After a system is selected, the user clicks the Revit download link to download a Revit template file that contains the USG wall family types. After download, the user can simply copy/paste a single USG wall assembly from the template into their project. Alternately, all of the wall assemblies can be copied into a project using the 'Transfer Project Standards' tool.
Revit Architecture users can download USG wall system directly from the USG Design Studio.
In the newly downloaded wall family, several new parameters are added to the wall family type properties that are specific to the assembly type the user selected. In walls tested for sound performance, for example, parameters are created for the Sound Transmission class (STC) and sound test number. Assemblies that were tested at Underwriters Laboratory (UL) have a link to their online certifications directory for the complete fire rating information.
Content downloaded from the USG Design Studio contains manufacturer-specific data such as the assembly sound test number or STC.
In addition to BIM libraries, the site also includes DWG-based components, links to assembly animations that demonstrate design and installation attributes, links to USG product and data pages, and specification templates that users can download and incorporate into project specifications.
Why has USG invested the time to create and maintain this site? As Steve Martinez, a technical support manager at USG puts it, "We are changing the way we call on architects. By connecting them with Design Studio, we can help them to specify the system they want and, in a few mouse clicks, incorporate that exact product data directly into their building information model. Before Design Studio, a process this complex wasn't possible on a real-time basis."
A Building Trend
As the use of BIM continues to grow, it's anticipated that more building product manufacturers will follow USG's lead and provide tools and libraries that enable designers to easily integrate manufacturers' products in their building information models.
This is a win / win situation for the building industry. Architects and designers gain more building choices and richer product data to use throughout the building design process, and building component manufacturers can convey product information directly to their customers more efficiently and effectively.
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