Building Products in BIM
Quality of BIM Content
Due to the large number of people creating BIM content and the lack of a consistent standard for doing so, the quality of content is a constant concern for users.
Working with the BIM Forum (bimforum.org), McGraw-Hill Construction conducted BIM Content research with approximately 400 BIM users. Responding to a question about quality issues with BIM objects, respondents rated the top five leading challenges (see chart):
The issues of managing what BIM content should be used on the firm's projects is a major part of Tim Logan's responsibilities at HKS. Based in the firm's Dallas headquarters, Logan manages the firm's central library of standard BIM content. He also builds a large amount of content for HKS project teams, and reviews objects proposed by HKS staff for library inclusion.
Asked about issues of BIM object quality Logan recalled a model of a warming cabinet that was produced by its manufacturer and is currently available for download online. "Something like that should have a file size of no more that 700K," he says. "This one was 5MB. When you think about how many of those might be in a major hospital project you quickly see the huge impact it would have on overall file size and slowing down the performance of the BIM software." As it turns out, the content creator had not understood how to use the BIM software and had nested many separate versions of the warming cabinet inside each other until the overall size was unwieldy. To use it, Logan was able to strip it apart to isolate a single cabinet that was about 1.2MB. That, however, required skill with the BIM software that many average users do not have.
Some BIM content configurators address this by giving users a hierarchy of options for level of detail (i.e., how much information they want in the objects), from very schematic for design to highly detailed for downstream fabrication. A record of the product selection is maintained on the configurator so downstream users can generate BIM content that is appropriate to their workflow needs.
Similar to the establishment of CAD, the increasing maturity of BIM will generate best-practice approaches among users, software makers will provide more capacity and flexibility to manage rich BIM content, and the further development of standards will provide guidelines for content quality that will control its creation.
Incorporating Business Rules into BIM Content
Just because a parametric BIM object can be sized by the user doesn't mean it can be realistically manufactured by the BPM. Jurgen Schroeder of NanaWall says, "You can stretch the models to create panels that are over four feet wide, which is not technically possible." He is pleased that "about 99 percent" of the users of the company's BIM objects stay within constructible limits of their products, but support is available for those who need technical advice to conform to realistic manufacturing limits.
Several of the online configurators include business rules in the software to notify the user about potential structural or other product failure issues prior to final acceptance and creation of content. For example, some online configurator tools will flag potential warranty issues as product layers are being configured for an assembly.
Survey of BIM Users About Demand For Types of BIM Content | |
BIM Content Category | Priority Rating (1-100 scale) |
Structural elements | 78 |
Plumbing Fixtures | 75 |
Mechanical elements | 75 |
Stairs & Railings | 75 |
Curtain Wall / Storefront Systems | 73 |
Basic Windows | 70 |
Basic Doors | 68 |
Elevators | 68 |
Electrical elements | 67 |
Roof Accessories | 65 |
Sunscreen/shading devices | 67 |
Civil/Landscape eleme | 59 |
Furniture | 59 |
Source: McGraw-Hill Construction |
Integrating BIM Content with Specs
Ideally, specification information would either be in or linked to the BIM objects. But at this point most project teams are still creating specifications as a stand alone document and only leveraging the BIM objects for their geometry and some of the technical and performance information.
Michael Brennan, CEO of InterSpec, whose software aligns specifications with other project documentation, including BIM objects, is operating at the juncture of this issue. The existing specification "is a legacy format we are dragging around with us," he says. He is hoping BIM shifts the focus to "the information about the product, regardless of the spec section it traditionally resides in. Rather than having this convention that says ‘I need this book,' with BIM we could just build this all up directly." This is especially true as BIM drives the industry towards whole building thinking for design, fabrication and construction. "Specs aren't about assemblies," Brennan continues, noting that an assembly could require reference to "half a dozen different spec sections. This evolution can't come quickly enough for me."
Justifying the Investment by BPMs
Where a number of BPMs saw BIM as an emerging trend and seized it to express industry leadership, many are still evaluating or conducting limited programs. David Bandi, Manager of Autodesk's Seek website for product content cites several major obstacles to BPM investment in BIM content. "BIM content has a level of complexity to it that requires a strategy behind it. It's not a cheap, quick and easy fix. Also, the lack of standards and varying definitions of what BIM is are confusing to BPMs. And even if they are ready, the timing question of when to do it is holding some back, perhaps waiting for more recovery in the building industry."
Some manufacturers do see a specific lift from BIM. NanaWall's Jurgen Schroeder is particularly enthusiastic. "Lately we are seeing our business really pick up from having BIM content," he states. The company is getting into foreign projects in China and Singapore through having BIM content that it would never reach through its traditional channels.
Notice
www.greenscreen.com
www.gpgypsum.com
www.nanawall.com
www.nystrom.com/Nystrom-BIM-Library
www.pellacommercial.com
www.ppgideascapes.com
www.bim.construction.com