An Interview with Daniel McFarland
In my Revit® and BIM, VDC travels, so to speak, I talk with a lot of folks about the transforming world of AECO and within these conversations I think it of benefit to give space here for a Q&A to colleagues whose considerations I find personally and professionally helpful. This year’s interview is with Daniel McFarland. With that in mind, I hope you too find some gold that you can apply to your part of the spectrum we call BIM. – Jay Zallan
Examples and Misconceptions
JZ: What makes great models great in the Construction phases?
DM: Great models are models that are coordinated with themselves and all other discipline models and continually progress in development, in response to and in concert with construction needs.
That said, one of the biggest misconceptions of modern construction is that there are still clearly defined, distinct phases to a project. I don’t see this as valid any longer.
Fast tracking and compressed schedules have blurred the traditional divisions of SD, DD and CD, CA. This may sound strange to many but consider it—we start building models using Revit during preliminary discussions with clients, even when initially studying feasibility and broad options.
To my knowledge there are a seeming few contractors using completely customized 3D estimating workflows, which helps set us and some others apart. Many of even the major construction firms begin with architecture and engineering models during SD phase; not us, we don’t or can’t always wait that long.
One of the reasons to use such a system is that we can in turn pass this information on to subcontractors who build their own model for permit, construction documentation, and fabrication from the original architectural and engineering models. Supplemental models will often be employed to keep track of and document changes to the original proposal.
Many RFIs from engineers and architects are handled with sketches, so those models will lag behind the actual construction design. Supplemental models help track changes and are often the only means of coordinating the multiple subs and consultants on a job. At the same time we begin the process of integration into Navisworks®, building custom search sets for clash detection and coordination of Federated Models, including models built by subcontractors.
Information that is developed in the creation of details needs to be pushed back into the larger context of the model. Changes in a detail can drastically change building scale elements. For this reason I am a huge proponent of taking the details directly from the model, with some added notation and fine detail in a detail view.
Often it is found that even in a BIM project model, changes to a plan will not be tracked through different portions of the documentation. An example would be changes in plan don’t get pushed to sections, elevations, and RCPs. As important as the 3D model is we still need 2D documentation for many reasons. Due to the diverse nature of communication and needs of different software, such 2D documentation is still hugely important, but must be dealt with at a higher level than traditionally has been found produced.
Focus | When?
JZ: Are there some suggested, valuable, yet often overlooked things that your teams model to great benefit?
DM: Our team will model things that are not often seen—things like stud rails, footing surcharges, post tension tendons, no-fly zones for parking clearance, door clearances, king studs, structural reinforcement, and sleeves.
We will often model these things as soon as we have useful design information. We prefer using 3D elements since it reduces the chances of error and they can be included in preliminary and ongoing clash tests.
These unseen elements have a huge effect on the design and the schedule. Giving designers of all types this information as early as possible is always a positive choice. Clearance zones, for instance, are useful when coordinating with Navisworks since they can be included in a clash test and conflicts can be quickly identified and planned for resolution.
Here in Los Angeles, we are in a substantial seismic zone and as a result heavy concrete shear walls are often used to resolve seismic loads. The services of the building MEPF often need to penetrate these walls with pipes and sleeves to run services up through buildings; models need to reflect this.
Such penetrations and sleeves can run as large as 10” or 12” or more in diameter, etc. An area of a shear wall containing #5 rebar (.625”) @ 4”O.C. does not leave room for necessary services without penetrations and sleeves, so each penetration in a given area may have to be engineered and detailed. Providing the visual locations of sleeves, etc. allows the teams time for early adjustment to the placement or replacement where and when possible. These construction-inspired design influences can see services routed to areas of sparse rebar, which can accelerate a project and save a great deal of time and money for all teams concerned.
Again, being a physical “no-fly zone,” these too can be included in simulations and clash tests for fast and easily understood results.
BIM Will Solve All Your Problems (and Other Fallacies)
Perhaps the biggest fallacy we find is that BIM will solve all your problems. It won’t.
BIM is inherently a collaboration process. It is a highly sophisticated collaboration tool but is only as good as its users. The best instruments in the world do not make a symphony transcendent alone—without great musicians, conductors, and the like, there would be no beautiful music; so too it is with BIM.
BIM won’t solve all your problems, but what it can do is help improve communication so you can solve your problems—often before they are problems. BIM facilitates, if not forces, more communication, information sharing, and collaboration. In my opinion this collaborative communication and information sharing are its major contributions to the building processes.
Gone are the days when a consultant could work without collaborating, and without collaborating responsively. Within BIM, the information is at every moment right there on the screen and/or sheet, if we only take a moment to look.
If we miss information, then chances are we have not looked at the plethora of information available to us; it can be as simple as that.
If in fact we do take the time to look at the information—starting early and continuing often—we find that such projects stand out and serve to make our lives so much easier, even as buildings become more complex.
JZ: Do you have advice for improving modeling or efficiency?
DM: One of the things I have seen on successful projects is to have a simple QAQC regimen; for instance, have someone unfamiliar with your model review it once a week.
Yes, I did say unfamiliar!
Thirty minutes can do wonders toward finding sloppy mistakes that we all can make and overlook. Often we become so familiar with something that we don’t see the errors.
Our brains project what we expect to see and not what is actually in front of us much of the time. I have heard of artists turning a canvas upside down to see their work in a new way. Not terribly functional with a computer screen, but by having someone unfamiliar with the project look at the model and sheets they can and often do quickly notice errors that we have become accustomed to seeing and overlooking. This ongoing process, carried out over just a few weeks even, has been proven to drastically improve model and team efficiencies.
JZ: Will you (and if so, when) repair architects’ and/or engineers’ models?
DM: We leave the architects’ and engineers’ models untouched. Full stop.
If there has been a major change to the project that has not been updated yet, we will remodel that element in a supplemental model. It’s a simple exercise to hide the original incorrect portion of the original model in Navisworks. This way we don’t disturb the intended and official nature of the author’s work and yet we can achieve the desired effect of having a correct model, thus a correct set of models for coordination, estimating, etc.
Supplemental models will contain anything from a few elements to major portions of a building. If and when the original model gets corrected or further development takes place, then parts of the supplemental model(s) can be removed from the process.
Conclusion
To wrap this up, I will paraphrase a few of my favourite quotes and send you off to create great(er) Revit models and more and more coordinated BIM projects!
- Great models are models that are coordinated with themselves.
- Information that is developed in the creation of details needs to be pushed back into the larger context of the model.
- Our team will model things that are not often seen.
- (Objects) being a physical “no-fly zone” too can be included in simulations and clash tests for fast and easily understood results.
- The biggest fallacy we find (in BIM) is that BIM will solve all your (AEC) problems.
- Our brains project what we expect to see and not what is actually in front of us much of the time.
- We leave the architects and engineers models untouched. (Rather) we will remodel that element in a supplemental model.
About Daniel McFarland:
Computer Graphics and Technology are driving forces to Daniel McFarland, who studied Architecture at Arizona State University as well as continued his education at the University of Texas’ Computer Science Dept. and the Texas Advanced Computing Center (TACC), #3 in the top 500 Super Computer Sites at the time. Daniel has worked for several high-profile architects including Daniel Libeskind, Michele Saee, and Gensler and is currently a BIM Technologist at Hathaway Dinwiddie Construction Co. in Los Angeles. He has a deep interest in technology, visualization, and architecture and is proficient in several programming languages including CUDA, C++, Python and Open GL. Daniel has been involved in SIGGRAPH and served as the Austin, Texas SIGGRAPH Chair. He is highly proficient with several software packages including all varieties of Revit, Maya, 3ds Max, Inventor, InfraWorks, ReCap, Mari, Nuke, Visit, Paraview, GCC, and Matlab. He has also worked for RTT USA, several major movie studios, and served on several film projects including Dome and 3D films. Daniel is well known as a Rendering Technical Director and for his computational photography.
