Asking for LOD alone is not enough

LOD, or Level of Development, is the system for classifying the amount of geometric detail within a model as set forth by the AIA’s E202 documents. James Vandezande has a great post on it from (believe it or not) 2008. The post does a great job at describing the different levels included, 100 to 500, and gives good reference to their intended meaning. Having used this systems on several projects now, I wanted to offer some feedback.

A few years back, when beginning to work on the Louisiana Museum and Sports Hall of Fame, I was inundated with emails and calls from just about every trade trying to figure out what constituted an acceptable deliverable. As the BIM Manager for the project, we were in charge of defining the requirements for a model deliverable that would be efficient, but also meeting the spec requirement for an ‘algorithmic coordination process’.

That project had another requirement that had a big impact on this conversation. The more than 1,000 unique cast stone panels had a surface integrity performance criteria that could only be achieved through CNC manufacturing. The fabricator, then, would be forced to model the panels and then use these models for mold making. This created a precedent. One of the more difficult elements in the design didn’t even have a choice but to create fabrication-level models. Did this requirement extend to the rest of the trades?

What if a trade wasn’t going to use the model for fabrication? What if they didn’t have the capacity to do so in their shops?

What became instantly obvious was that there was an ocean of space for interpretation in the LOD system. The specs called for an LOD400 model to be developed in the service of coordination. An LOD400 model is one that contains ‘shop drawing’ or ‘fabrication’ level of information. There was one big problem with this definition on this project, however. The lack of an explicit requirement on the model’s intended use left a gaping hole in the spec for a participant to interpret as they saw fit.  One company’s view of what makes a good shop drawing versus another can be very different.

The lesson then was to not just ask for a deliverable, but to also ask for that deliverable to meet a certain level of performance. A model used for fabrication will inevitably make for a model that is accurate for coordination purposes. The opposite, however, is not always the case.

In this project, the hook was to also ask that all information presented in shops (the legal document) also be present in the model. This way, the architect could use the model as a real reference in their shop drawing review process. The importance of this requirement was that it ties their legal deliverable with the BIM process. This made BIM central to their every day project management knowing the architect could reject a submittal by virtue of their model quality or completeness.

This move though would not work on many projects and is hard to enforce.  A better way to define model performance is to actually tie the deliverable to a good performance specification. That performance specification would include a reference to LOD. It would also include a responsibility matrix (the MET in the E202), and an intended use matrix. These three elements together make for a much better definition for model deliverables.

A good BIM execution plan (BEP) should include all these documents and a framework for their implementation.

Repost: Why the maker movement is good for architects

This is a repost from our Practice 2.0 column on ArchDaily (original here). Originally posted on June 15, 2011.

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by Federico Negro

Earlier this year I had the following experience. Two friends, the first a lone (and successful) entrepreneur whose company brings kids books to the iPad, the other a banker, both asked what I knew about 3D printing… on the same day!

What was going on? Where did the sudden interest in 3D printing come from? 3D printers had been a staple in architecture schools and many offices for years, so I assumed everyone knew about them, no? Confused, I did what I usually do when faced with the unknown. I asked Google.

Of course…! Two days earlier The Economist had run a feature on the technology (link and link) and Business Insider was proclaiming it as the “Next Trillion Dollar Industry!”. Even the New York Times got in on the action. I started digging around a bit more and quickly realized something amazing was actually happening…

The Maker Movement had gone mainstream.

So what does this have to do with Architects? Well, architects and architecture schools have actually been very quick to embrace the concepts and technologies surrounding digital prototyping, and have adapted their curriculums accordingly (not all of course, but many). The reasons for this tend to vary depending on who you ask, but there is certainly no shortage of additive or subtractive processes in design exploration today both within schools and without. Many schools tout incredibly sophisticated shops, and even use them as a recruiting tool. ARCHITECT magazine even has a ranking of the best US schools for those interested in Digital Fabrication with Ball State University sitting at the top mainly due to its Institute for Digital Fabrication, followed by SciArc and the University of Michigan. This has made architectural education incredibly well adjusted to both participate and take a leading role in the maker movement.

There are two forces fueling the expansion of this movement. The first is a market-driven demand for digital manufacturing technologies to become more economical. We’ve seen this really take shape in the last few years. 3D Systems (an NYSE listed company: DDD) already offers professional printers for as little as $10,000. Architects are taking advantage of this and are tooling up their practices. For about $6,500, the Shopbot Desktop can expand any architect’s shop to include a 24″ x 18″ x 2″ CNC that can cut through wood, plastic, aluminum, etc… For those with a bit more advanced needs, you can even have your very own compact 5-axis for less than $40k…

The second, and probably more interesting force, is the boom in open source technologies that have pushed the barrier to entry down even further and have expanded access to a much larger user base. Lumenlab offers a desktop CNC for under 2k. You can even find open hardware projects on Kickstarter that will send you kits to build your own CNCs for less than $500, not to mention Makerbot‘s success with its popular open source 3D printer, which has taken its founder, Bre Pettis, all the way to the Colbert Report.

On the input side of this movement (3D models), we see a similar divide. Sophisticated tools like Solidworks are typically considered too difficult and too expensive for large scale adoption. Rhino, one of the more popular tools for architects, has done more than its part in democratizing 3D modeling and lowering the price barrier, but may still be too niche for the general population. Google has gotten into the game through SketchUp and has been more successful in attracting a wider audience (it helps that the free version has more than enough functionality for most of these users). Autodesk is also trying to get into the game with the introduction of 123D, a free (yes, free) implicit parametric modeler marketed to ‘makers’ (video of Carl Bass, CEO of Autodesk with Wired Magazine’s Chris Anderson). Not surprisingly, some of the best users of these applications are architects…

With economic barriers being lowered every day (or having already hit bottom), the missing ingredient seems to be general widespread access to good design, good models, and good engineering. It is in this missing ingredient that we, as architects, should see the most potential for impact. Sites like Shapeways, i.materialize and Ponoko are trying to attack this problem directly by connecting consumers with designers and fabricators more efficiently, but focus more on consumer goods. GrabCad is a good model for us since it is both industry specific and highly technical. Is there an opportunity for a building industry equivalent?

Current technology trends like building information modeling (BIM), parametric modeling, fabrication modeling and energy modeling coupled with the architect’s natural tendencies toward ‘making’ are coming together to create highly valued professionals with highly relevant skill sets. These professionals have the opportunity for great impact, helping expand the value of the services and products we offer and reshape our industry in the process (see previous post).

We’ll continue to track these tendencies as we move forward and report back on its innovations. For now, I leave you with eleven 3D printing predictions for 2011 and the third of my favorite do-it-yourself videos…