Posts Tagged ‘graphics

27
Jun
08

BIM Revolution Not Quite Here Yet

An interesting article in The Economist suggests that the revolution in BIM (Building Information Modeling) is, at least for the present, mainly wishful thinking. By and large,

… fancy graphics tend to be used only for conceptual purposes and play no role in the detailed design and construction of the finished structure. For the most part, this is still carried out with old-fashioned two-dimensional elevation and plan drawings, created by hand or using computer-aided design (CAD) software. “It’s still a 2-D profession,” says Shane Burger, an associate architect at Grimshaw…

With CAD, you draw your picture, and the software makes it malleable, so it can be changed, added to, combined with another. With BIM, you put in the facts of the case and tell the software what you need, and it draws the picture. It seems that many practitioners are still in a CAD headspace, unable to make the leap of imagination that would really put BIM to work for them.

When the client says, “How will it look from over there?”, the elegant and stunning pictorial answer can be shown, and that’s cool. But there’s so much more to BIM than dazzling graphics. The amazing virtual walk-through is negligible compared to the real power and beauty of BIM. The thing to keep in mind is that a building information model is a digital representation of both the physicals and functional characteristics.

Traditionally, one of the embarrassing possibilities, once construction starts, is discovering that a basic law of physics is being violated, as two things, such as an air duct and a beam, try to occupy the same space at the same time. In building information modeling, the word “information” is there for a reason – because the best part of BIM is the huge database of everything you could possibly want to know about every part of the building at all times. Like the weather or any other system, a building is subject to the so-called “butterfly effect.” Tweak something over here, and something over there is affected. With BIM,

the model is based on objects, which are solid shapes or voids with their own properties. The model also includes information about the relationships between these objects, so that when one object is changed… any related objects are automatically updated.

In a large project, the number of stakeholders can grow to monstrous proportions, and BIM keeps them all on the same page. Time is an added dimension, so processes can be followed through the life cycle of the building. All the stages of design, construction, and facility management are taken into account and automatically updated. Energy use, lighting, heat flow, acoustics, and many other factors can all be kept track of. The most important thing is the sharing of resources and information across platforms and environments.

The author points out that the early adapters are the more flamboyant, high-name-recognition architects. Because their creations are so complicated and unusual, there’s really no other choice. What’s needed is BIM across the board; it needs to be a plow horse as well as a show pony. Apparently this is happening, as the General Services Administration now requires BIM technology for all the projects it funds.

Of course, accurate cost estimation is a huge incentive, now more than ever. When the digital prototype is the main reference, it’s possible to calculate very finely the quantities of materials needed. Perhaps even more important, every detail necessary for compliance with regulations is spelled out. MIT professor William Mitchell estimates that inconsistencies and clashes can eat up from 2 to 5% of a budget. This is interesting, because that’s about the same percentage range as it costs to make a really good green building. So, thanks to BIM, it seems that a building could be made greener (costing 3% more) and smarter (saving 3%) and still end up with about the same price tag, when all’s said and done. With the cost of energy and materials going up, and the cost of information going down, it looks like the BIM revolution will go forward.

Pictured: the Eden Project, in England. The geodesic domes were BIM-designed.

SOURCE: ” From blueprint to database ” 06/05/08
photo courtesy of just_laze , used under this Creative Commons license