It’s Not About BIM

September 8, 2011

A construction model is about construction communications and not design.  These are simple 3D and 2D models that can be staged and sequenced to illustrate a technical process that many (if not most) designers don’t really understand.  It’s simply not what they’re paid or trained to do.

Design engineers and architects use complex building information models (BIM) to document the requirements for a completed building.  Instead, a construction model is a graphical tool used to visually manage the construction process.  The model frees constructors from a tradition of diagrammed dependencies that often leave them on the receiving end of a one way conversation.

Insitebuilders-Field Drawing Example

A simple visual explanation
For example, imagine what would happen if a builder pulled a pencil stub out of his or her tool belt, grabbed a scrap piece of paper from a trash pile, and used it to sketch a detail for the designer to take back to the office and draft.  With that drawing, the builder just stepped back into a time when visual explanations were a natural part of construction management.

The “art” of scratching lines on the earth, marking corners with stakes, and notching stones with chisels stands at the Paleolithic beginnings of construction.  The earliest construction drawings were prehistoric ideograms, visual gestures used to represent an idea that needed no words or dimensions to layout and complete the construction.

Insitebuilders-Ancient Quarry Marks

In the field, chisel marks, mockups, strings, and plumbs were used along with chalk, straight edges, and protractors to physically layout the work.  These were spontaneous graphical devices that builders used to manage the construction process.  Important is that the workers using these visual tools were builders and not designers, markings and models were part of the way buildings and bridges got built.

Evolution of the explanation
Somewhere in the evolution of construction communications, these early field markings were scaled to paper and parchment and what was once a working drawing became a contract document.  As such, field drawings became technical representations, drafted to stand as an abstraction of values and no longer seen as a tool integral to the flow of the work.

As a result, diagrams and models that were once used as management tools, drifted away from early builders to become their own kind of technical art.  Drawn by skilled draftspersons, first with pen and ink, then vellum and calibrated pencil, Mylar and waxed lead, and eventually vectored lines on a computer monitor, these documents became the dominant voice on the jobsite.

Insitebuilders-BIM CAD Drawing Sample

Today drawings and specifications are extracted from BIM models, plotted on reams of paper, labeled as “information,” and distributed almost as an after thought to the subcontractors and workers in the field.  What was once a straightforward visual explanation has become a static construct, built to reference the legal requirements of a contract, obfuscated to a point where many experienced designers no longer need to understand how to operate the underlying model.  The result is tedious, even for those trained and paid to perform….

Untangling ideas
Output from the BIM remains as a graphical explanation, but the drawings are now much too deeply entangled in their own internal complexities for any real collaborative input, especially from workers trying to put something together in the field.  This means alternatives that could once be considered and grudgingly erased and redrawn by a draftsperson, must now be painstakingly reconstructed within the layers and references of a complex model.

Insitebuilders-BIM Example

As a result, a BIM model is simply not intended to spontaneously respond to new ideas.  Instead, it anchors a preconceived approach into a muddle of memory and menus, creating the illusion of a collaborative process.

Real-world collaboration only succeeds when simple explanations can be generated on the fly, well before they’re cast into the murky depths of a model.  This might still include the stub of a pencil and a scrap of paper, but on a post-modern jobsite, it’s just as likely to include a tablet computer and a few taps on an open-source program, capturing and communicating process-alternatives using a straightforward construction model.

Insitebuilder-construction detail array

BIM is a design tool
In short, simple construction modeling programs (like SketchUp) do not even come close to challenging the entrenched commitments most firms have for BIM technology.  Output generated from a designer’s BIM models are contractual statements of static intent, rendered as a motionless landscape, representing the finished product.

Insitebuilders-Visualize Construction

In contrast, quick and simple construction models are used to generate animations, study sequences, and capture images in order to manage the flow of the work.  That means they support real-work in real-time, fulfilling the real-need for immediate visual explanations on a real-world jobsite.  The same explanations once found in an ancient tradition of graphic communications in construction.

See also:


4 Responses to “It’s Not About BIM”

  1. Ed Says:

    It is all design. Understanding architecture only comes by knowing that if one cannot conceive of something, then one cannot draw it, if one cannot draw it, (on drawing board or on a computer) then one cannot built it. Drawings are paramount. Drawings are the means to architecture.
    Construction Documents are only a short hand method used to communicate to a skilled builder – it is all they need. I like and have used your product; however the idea that any computer aided design program substitutes current creative/technical process is flawed. The beauty of proportion, the beauty of arrangement only exists because of the beauty of drawings – design and technical are all the same. It is all design.

  2. Dima Says:

    Common, buildings are more complex, therefore it is more complicated to document them. On top of that any mistake can be a reason to take you to court and that is the reality whether it is a good thing or not. Sorry, but “the stub of a pencil and a scrap of paper” is not a solution anymore. How are you planning to attach the information created by “few taps on an open-source program” to your project documentation?
    And regarding “a BIM model is simply not intended to spontaneously respond to new ideas”. As far as I know most of the BIM packages are parametric in their nature. That is by far the most change flexible tool concept in the long history of construction. Wow, the concept of parametric relationships between elements in most common BIM packages was introduced exactly for this particular purpose – to respond to changes (whether they are driven by “a BIM model is simply not intended to spontaneously respond to “new ideas” or anything else). Parametric thinking, how is SketchUp going “to spontaneously respond to new ideas” in your opinion?

  3. jeremywo Says:

    I have a question about one of your drawings – the construction detail showing a perspective view of an assembly with planar detail pieces intersecting it. Is this in Sketchup? If so I am curious to know how you accomplished this. If you don’t mind sharing. Thanks Jeremy

    • insitebuilders Says:

      Those details are imported scanned 2D images (into SketchUp). Two tricks:

      1. Import each image into a separate file in SketchUp so that they can be scaled. If you try to scale them in the main model SkUp will scale the entire model. Use some known dimension in the model to scale, similar to this video:

      2. Be certain to explode and then group and rename the images after import. That will make them visible as a texture so you can crop and manipulate the image. You can then cut and paste this new group into your main model, set up invisible guidelines to position the image) and slide it into place. If you want you can even section the model itself into pieces so that you can animate the details (see the article on Scenes and animations)

      Good luck and let me know if you have any probs


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