A very key advantage to Building Information Modeling (BIM) is that it helps to deliver the promise of prefabrication. Complex construction projects ( I’m talking about things way more complex than a typical single-family residence) designed and built from 2D drawings suffer from information anemia. It becomes extremely difficult to know for sure if everything is going to fit into a given space, especially since multiple trades often design their installations within the vacuums of their own minds.
By using a BIM approach everybody shares their plans, and so collisions and space requirements are worked out before construction begins. That gives rise to a whole new level of potential efficiency where complete units, with all of their attendant plumbing, electrical and HVAC, can just be dropped into place and connected. And that can be done with a high degree of certainty that everything will fit, and connect to what it is supposed to connect with.
As the advantages of prefab components are realized more and more during the construction process, architects and engineers will start to see more design opportunities in prefab as well. This is where generative fabrication (GF) begins to extend the advantages of BIM. Not only does it allow the quick creation of multiple, identical components, but it also allows the creation of structural members that permit design to come to the forefront. (Photo Courtesy designtoproduction)
People are making things using GF by connecting parametric CAD systems to computer controlled fabrication tools. In the case of timber the tools are mills, drills and cutters. This is the advent of what is called “mass customization” for the building industry.
Not only are complete building assemblies being created this way, but the door is also open for highly customized building components. Take lighting for instance. MyLight can be different for every person because it is not created from a mold. Instead it is fabricated through three dimensional “printing.” As the creators say:
We can now “print” an object directly from digital information. People have no idea yet what an incredible change in technology that is, and what that means for design. All design will become meta-design: objects can now be a range-of-objects, like in a family or a species.
The computer controlled machines that make these items come in a variety of forms. Stereolithography machines make things from plastic by building them in layers. The plastic is polymerized layer by layer using laser light. Selective Laser Melting is used for fabricating items from metal. Again, the metal is applied in powder form, in layers, and is made molten by laser beam energy.
For those of you who want to get a glimpse of the future, from August 3-7, in New Orleans Siggraph 2009 will showcase some of these generative fabrication concepts along with some of the things that have been built using them.