The End of CDs?

As an architect of a certain age I have distant memories of my first assignments in an architectural office, when finally offered a desk and chair (versus running prints and making the twice-daily Coke run).  They were almost invariably something connected to the making of working drawings:  practicing block lettering, tracing details, starting with rudimentary drawings of small portions of the building (like the toilet partitions), then moving to drawing even larger portions (like the entire toilet plan), to entire plans, and so forth.  Learning th discipline of analog architectural drafting—a mostly lost art form—was the spanking machine through which one passed to greater responsibility in the office.  At least for me, it was never the other way around: being assigned to help conceptualize a project came much later (although making presentation drawings and building models might punctuate the time spent on those toilet partitions).

Years later, as my drafting instruments sit mouldering in my desk drawer, the age of integrated delivery via BIM is calling into question the very existence of traditional working drawings, and with it some of the methods by which young architects learn the craft of putting together a building.  We’ll leave the latter topic to a subsequent post, and consider here some early thinking why working drawings, or “CDs” might be going the way of their audio counterparts.

Before examing the question, first consider exactly what a “working drawing” is supposed to do, and how it might be positioned in the design-to-build continuum.  Since designers under Western construction models are responsible for something called “design intent” (a general description, with discontinuous levels of detail, of what the building should be when finished) and builders for “means and methods” (figuring out the coordinated, procured and sequenced means to make the building) there is a natural division of labor and a constant source of tension, controversy and litigation.  Before the age of plaintiffs attorneys, super-complex buildings and viciously low-margin bidding, this wasn’t really an issue—architects knew enough about what contractors needed to build to provide sufficient information in CDs and contractors knew enough about how to accomplish those aims that most projects flowed with reasonable smoothness.

In the main, none of that is considered true today, and the oft cited statistic that “92% of owners think architectural working drawings are insufficient for the purpose intended” (CMAA Owner’s Survey 2005) is a symptom of larger pathologies that the integrated delivery movement is designed to address.  The principles of BIM-enabled integration, however, suggest that the notion of “final design documents comprise design intent only” is under siege, and perhaps rightly so.  Early builder involvement, high resolution parametric model content, integration of shop drawings into CDs, fast tracked packaging, performance specifications—all this stuff will eventually morph what was the “Construction Documents” phase and the “Bidding and Procurement” phase into something else entirely.  It might look something like this;

1. As sub-contractors are involved earlier in the design process, their insights, translated into what was once known as shop drawing levels of resolution, can replace large swaths of “design intent” information.  This is happening today when MEP sub-contractor fabrication information finds its way directly into the final documents, and the single line diagrams and 2D ducting plans of yore disappear.
2. Once constructors are more fully integrated into the design process, documentation will be “reverse engineered” from construction outcomes rather than “refactored” from design documents.  What was once a set of CDs organized by the originating discipline (architecturals, structurals, electricals, etc.) will change into packaging that supports specific construction strategies and will likely look more like bidding packages (foundations, superstructure, enclosure, finishes, etc.).
3. As model-based information replaces traditional 2D documents, everyone can access the database of design information and extract or cross-tabulate whatever information—geometric or otherwise—might be necessary for their particular component of the work.  This means the “abstract notations” that have been created to make CD documentation efficient (like wall type indicators) are no longer needed.  Whomever is building that wall can find out pretty much anything they need about it by referring to the model. Who needs a drawing?
4. As digital fabrication techniques for selected building systems (like for example, curtainwalls) becomes more prominent, interpolating architectural and structural information to “understand” that system so it can be machine manufactured makes little sense.  Information willl need to be organized and extracted to drive that process first and foremost.

So these are just a few musing about why what we now know as “CDs” may be something entirely different before my drafting instruments pass along to my children as part of my estate.  Perhaps the “CD phase” will give way to something new, like the “Implementation Documents” phase, as certain IPD constructs suggest.  In any event, I suspect that the days of making diagrams of toilet partitions as the port of entry to the technical documentation process will very soon disappear completely.  And it’s probably about time.

 

Comments

[Paul]

Hi Phil,

Great post.

I agree that the design coordination of the building project can largely be done through BIM. However, I can see us using drawings for the manufacture and installation of building elements for a while yet.

This is largely because individual tradesmen don't want or need access to ALL the information. All they need is a clear instruction of their next task or process. Drawings fulfil this need perfectly.

Paper drawings have the added advantage that they boot up immediately, they work even when they are dirty, trodden on and dropped, they never run out of batteries, and no-one is likely to nick them!

Keep up the good work,

Paul

[Phil Bernstein]

Thanks, Paul. I agree with your logic, and I doubt a several thousand year-old tradition will disappear from our process any time soon. And high-resolution, coffee-proof, easily reproduced and cheap pieces of paper make sense for all the reasons you outline. Of course, the real question: how, exactly, do we produce that paper? Certainly not with compass and rule...

Phil

[DMaser]

Phil, I really enjoyed this post. I am working as a Virtual Construction Engineer/Visionary with a large CM firm. One of the ideas that I came up with was to develop drawings just as you are talking about here. Maybe not completely eliminate a design side set of CD's, but I am also creating what I have began to call trade specific data sheets for each room of the building, for each trade. Consolidated information the way that each trade wants to see it for each room. It's been a big plus so far. Elimintaing the process of leafing through multiple drawings to build one room, or calculate what quantity of material they need for that room. I believe BIM is about not only the information, but having the information you need to see it.

[Barry]

Hi Phil, very interesting. I have recently crossed over to help out on a large Interiors Convention Centre project. I like and agree exactly what you are saying, but how do you think, with this new direction in mind, people will verify and confirm the quality of the work that consultants have contributed to the BIM model. Recently , we had an AV consultant, take existing Interior and Architectural plans and place his work into it (speakers, projectors, cameras etc) and submit it. But only upon printing out and look at each instance of his work did anyone come to realize how shockingly ill coordinated and inappropriate all his work was. Its true that better coordination here may have got rid of the problem but only through his prints did all of this become apparent on a project with many other consultants.
Im curious to take this subject further and look at what the new "Design Intent" phase may now include.

[Warren]

Phil,

In reading the artilce I was intrigued by the notion that CDs may pass into extinction. Intrigue however quickly morphed into anxiety that our "standard of care" as Architects may also be changing. At what stage are we required to leave our safe harbors and engage in the realm of "completeness"? Scary.

And, I wonder how new generations of Architects will learn to understand the way a drawing is crafted (in its individual sense of art). That is, how do we teach young architects to use lineweight, linetype and hatching to convey what BIM doesnt automatically generate? All those years behind a drafting table give you the eye for proportion, development of cosntruction lines into real lines and overall sheet organization. It is the skipping of these fundamentals that concern me. Are we to assume that the physical drawings are now also passe? Are we now facing the extinction of 2D representation of a 3D world?

[Balazs Trojak]

Hi Phil, thank you for a reassuring article. The purpose of drawings to be clear and targeted conveyance of information was well undestood in the past. On the flip side BIM enables us to assemble anything and everything into the model creating magnitudes of complexity. This emerging gap is seen by our clients who increasingly comment: "too many parameters", "too much data", "too much detail". We have to deal with this as a daily routine. I like the analogy with "reverse engineering" to extract data from the BIM. The winners will be the ones who can best manage complexity and make the data accessible to Everyone in the process.

[Phil Bernstein]

There are several really interesting comments here, much appreciated, and each connected to the issues of how design information is defined, organized, displayed and transmitted for purposes of construction. I think my vague assertion is that each will evolve accordingly. Of course drawings--super fast, cheap, and abstract--will remain important, but the other forces at work must force us as architects out of our "safe harbor" into more turbulent but much more interesting and valuable waters where we can add (and extract) real value. It seems that some combination of the digital, three-dimensional, parametric, and data-driven will move discipline-based drawings ("the structurals, the mechanicals") to trade-based integrated representations that would obviate the problems with the AV consultant that Barry describes above. It's the need to refract the work exclusively through that discipline lens--and drive everything from business model to drawing organization to risk management approach--that is at the heart of this issue, overlaid with the obligation to manage levels of abstraction versus detail. And as the line between design intent and execution gets ever fuzzier, new ideas for how to solve this puzze will emerge. That's what I'm hoping will happen!

Phil