BIM - The Craze of Building Information Modeling 7

[ash060]

A while back I attended a Revit Seminar at my office. I was slightly impressed with its capabilities, but it seemed to not be that popular. Now every engineering magazine that I get is talking about how awesome BMI is, but I have still not encountered anyone who is doing it. I have not met one architect that has heard of it. Has anyone had any experience with projects where all the consulants are using a BMI software, and if so is it really all it is cracked up to be?

 

[jeffandmike]

I guess I'll be the one to stick my neck out here (and no I don't work for Structural Engineer magazine or any of the BIM software manufacturers).

I'm a CA licensed civil and structural engineer and the head of the building design department at our company. Our department takes designs from concept to a permit set of plans (including complete 3-D modeling, architectural design / plans, structural engineering design / plans / calculations and energy calculations).

About a year and a half ago or so, we started the migration to BIM. We've found that the time / cost to obtain a complete architectural plan set (from only a design concept) has been cut in half, while providing additional value to the client (they now have a 3-D model of their structure, whereas previously they only saw things in 2-D).

Not only can the 3-D model be seen on the computer, if the client would like, it can be used to create a (scale) physical 3-D model (like a dollhouse) of their structure using stereolithography. The correct colors / textures can even be added to the model.

Additionally, BIM keeps improving all the time. For instance, once the model has been correctly created, energy calculations can be performed more quickly and accurately (right from the model).

Also, the ability to analyze the model structurally is becoming more and more popular, with better support from software manufacturers all the time.

Sure we had to teach all of the old dogs new tricks, but once they learned 'em, they now have new tricks to showoff. I'm not going to make light of it, though. It has been a difficult learning process for everyone involved and has required much patience. Of course we've really only made it up to 3-D at this point (not 4-D or 5-D yet, though the software has the capability to).

I can't fathom ever going back to 2-D CAD. I really can't understand how anyone (today) can survive using 2-D handdrafting! When I think back about how inefficiently we used to operate, it boggles my mind.

If you draw architectural plans in 2-D, how many times do you draw (or create a placeholder for) the same window or the same door . . . once in the floor plan, once in the exterior elevations, maybe once again in an interior elevation, possibly again in a cross section, and maybe even again in a detail? When you draft in 3-D (BIM), how many times do you draw the same window / door . . . once!

BIM can also help elimate costly mistakes.

My two cents . . .

 

[ron9876]

Yes but you are addressing mostly the drafting aspect. I can see where it may be an advantage to architects but structural engineering is mostly calculations with drafting a somewhat minor part of the process. Architects typically do their own drafting with graduate and experienced architects but, at least in my experience, structural drafting is done by technicians. To switch to using experienced engineers to draw doesn't seem practical to me and it has to cost more. There is a shortage of engineers in our market and this would only make that worse. There are also clearly some increased liability considerations. I also don't know very many clients that would really make use of a 3d model. Possibly government clients with a complex building but what use would a developer have for a 3d model of most buildings.

I am curious. Do you get a larger fee when you provide the owner with a 3d model and do you get some type of waiver of liability. Does your insurance carrier have any concerns.

 

[jeffandmike]

The 3-D model we provide to our clients is a "read only" version. It can be rotated around (viewed from all sides). A cross section can be cut anywhere they like. Additionally, any component of the model can be removed for a better view of the rest of the model. For instance, similar to how the roof on dollhouses can be removed for a better view of the inside, likewise the client can remove the roof (or any other component) of their virtual 3-D model. They can do all of this on their own, without our assistance, using a free software package. They can also print any view they want.

Again, though, let's keep in mind what they have cannot be modified by them. Once they're done "playing around" with the model, there's no way to save the changes.

The work product they are paying us for is the plans and calculations. The read / write version of the model remains our property and is only an "instrument of service" while the read only version is theirs to keep. I suppose if they wanted to pay us enough, we may release the read / write version . . . but not until we had a complete waiver of any liability associated with the model, signed by them. That being said, up to this point we have not released the modifiable version to any of our clients. We also already have a fairly enforceable limitation of liability agreement in effect with every one of our projects.

We do not typically command a larger fee for modeling in 3-D. As previously mentioned, what it has done is allow us to be substantially more competitive, though. We are working in a more efficient / coordinated fashion, keeping budgets better in check. Clients will often select us over the competition due to the provision of the 3-D model. We may not have otherwise gotten these projects.

Having the 3-D model is also beneficial once the project gets to the engineering stage. All of the structures we do (at this point) are four stories or less, usually light commercial and custom residential (concrete, wood and steel mostly) performed for private sector clients (we don't currently work for, nor have the desire to work for, government clients). Typically, these types of structures are not highly repetitive (like a parking structure or highrise) and can be very difficult to visualize in 2-D (at times). Vertical offsets in floor diaphragms, clerestories, multiple ceiling heights on the same story, complicated stick-framed roofs (think turrets, curved roofs, dormers, attic trusses, etc.), hillside projects with stepped foundations and / or retaining walls, etc. are all features that can be difficult for the engineer visualize / design for.

With an inhouse 3-D model, the engineer can (in about five seconds) cut and view a scale cross section on any part of the structure. The engineer can also (in about the same amount of time) have an interior elevation of any portion of the structure. Little details that may otherwise get missed by the engineer and may affect their detailing / calculations, get caught.

We are currently moving into exporting the 3-D model into structural analysis software packages (RAM or RISA, for instance) for analysis. Though the bugs are still being worked out, if one exports the model into RAM, a very thorough structural analysis (with calculations) can already occur. If changes need to be made to the 3-D model (say changing an assumed beam size or footing size), it can be changed in the analysis package and synchronized / updated in the architectural model.

 

[ron9876]

It is still hard for me to imagine that this would be more cost effective. Possibly if all discplines are in house it would be more valuable especially if the architects have already developed the model. It clearly would be an aid for MEP coordination with their layering of services. I don't think most structural engineers have a problem visualizing 3d conditions. Still if you are letting the suppliers use the model for their takeoffs there has to be increased liability because the picture has to be fully to scale. But I have been wrong before.

 

[archeng59]

perhaps I'm old fashioned, although I'm not that old. There are thousands of existing buildings that were successfully constructed without heavy computer usage. Perhaps the BIM is a generation gap issue. Those of us who have worked in the world without computers and design primarily using hand calculations and Enercalc, occasionally with STAAD, fail to see the benefits of having a design generated completely within a computer. The younger engineers working for me love the computer... it's their brain and all of the answers are obtained from the computer. they grew up with computers and want everything to involve the computer. It seems that if it cannot be done with a computer, it's not worth doing. The computer is just a tool to me. No better or worse than the pencil. I look at the use of computers like this: why string out and hook up an air hose and pneumatic nail gun to put a couple of nails into a board when I can use a hammer?

 

[Tomfh]

It will be cost effective soon and will become ubiquitous. You can't stop progress...

 

[prost]

If this newfangled gizmo BIM is similar to Six Sigma, TQM, and the like, it is possible that it also overpromises as TQM did. In a recent column by Dale Dauten, discussing what TQM has done for companies's bottom lines, a fictional conversation revealed this tidbit:
"...QualPro, a research company I wrote about recently, searched for corporations announcing new Six Sigma programs, then looked at what happened to each company's stock price. Of the 58 companies they reviewed, only six had stocks that outperformed the S&P 500, while 52 underperformed...."

This was my earlier point about the parallels between the craze of the past, TQM, and the today's craze, BIM. The Dauten column continues with the fake conversation, with the conclusion being that TQM is fine, but if it doesn't result in other changes in the company, its benefits are dubious at best. Like any change that requires a significant resource allocation, your company might benefit from BIM, and it might not. The difficulty is deciding if you'll eventually see a net benefit. It might seem to you that people are just fighting progress; most experienced engineers have seen enough of these fads come and go to be wary of any change that demands such an investment of precious company resources.

 

[archeng59]

BIM might be progress, but at this time I don't envision it to be in the same realm of progress that we could see before we switched from hand drafting to CAD, or moment distribution to STAAD or another stiffness analysis software package. Not all projects will benefit from 3D modeling or 3D drafting. I'm not against change if there is a real advantage. But I'm not in favor of change just for the sake of change to increase a software manufacturer's bottom line and decrease mine.

 

[ewh]

I feel like I walked into a luddite convention. I do not work in the civil field, but this situation is similar to what all of the mechanical designers and engineers were saying about CAD 25 years ago. "We've done great so far! We've even put a man on the moon using board drawings. This CAD stuff is just a passing fancy. It will never be cost efficient."
Today many large (and small) aerospace companies are moving toward a new standard in which items are completely designed and documented in the CAD model. MBD (model based definition) is not yet widespread, and I still here similar comments about how it will be to difficult to adapt to, but it is the future, and if you choose to ignore it and stay with what you are the most comfortable with, you will be left behind. The current situation with BIM is eerily similar.

 

[swearingen]

The key here is scale. I'm in the industrial field and we have 3D models in specialized software that we use to integrate the mechanical piping and equipment with the structural steel and concrete. It's a good tool on large jobs and can prevent uh-ohs late in a project if done right. However, on smaller jobs (say, less than $5mil TIC) it just doesn't pay to do the model for the structural department (piping ALWAYS uses it, for good reason). The individual teams can do their jobs more efficiently without it and coordination meetings can be kept to a minimum. We are not a tech-averse firm. We have our own 3D laser scanner (a $250,000 investment) that we use to collect field data and to build our models from. We just use it when it is practical to do so.

I have never done a commercial building, but I can't imagine that there can be enough complexity to pay for 3D modeling a CVS pharmacy. A skyscraper, a city landmark architect-went-nuts library, or a Wal-Mart can bring up the question, however. The skyscraper is large and fairly complex and managing the info could be useful. An architect-gone-nuts structure can be incredibly complex, even if it's fairly small. A Wal-Mart is about as close as you can get to a mass-produced decent sized structure, so economies of scale may kick in to pay for 3D.

To sum up, I say again that I really think it depends on scale in the building industry.

The aerospace industry is different in that every structure is complex, made from a huge number of differing materials, and requires a ridiculous amount of paperwork for tracking every tiny piece for certification. The high school summer I spent as a clerk on the shop floor of a helicopter engine shop taught me to appreciate that.

 

[BSE05]

Question for jeffandmike: What software are you using and what departments use it?

I read that structural engineers working on Gehry buildings draw in 3-d and give the electronic file to the steel fabricator. Can you imagine trying to draw one of those structures in 2D?

I've seen revit structural, but not convinced yet that it would save me any time. Maybe I'm just not ready to learn another program, being a SE for almost 40 years! I've done pretty good hanging in there to date, but now I'm ready for dinosaur status.

 

[prost]

Rather than a Luddite convention, sounds more to me like the voice of experience, experience of watching various trends and fads come and go, collossal amounts of money wasted on those same fads.

 

[bjb]

ewh, how many buildings have you designed?

 

[lkjh345]

ewh:

Sounds a lot like the aguements we heard 10 years ago concerning metric. We were informed, as a matter of obvious fact, that 'everyone' would be designing in metric in a few short years, and if you didn't get on the bandwagon, you would be out of buisness shortly.

How many people (in the USA) design their domestic buildings in metric today?

 

[ron9876]

It won't become popular for us conculting engineers unless the architects require it. It is fairly clear to me that the initial capital plus the added liability will make this very difficult to implement in the real world. By the way did you guys see tha article in the Structural Engineering magazine. Brought up some interesting points.

 

[BBENG]

I think people are confusing Revit software and BIM. A true BIM model will include everything that the final building will have in it including doors, structural system, MEP system, soap dispensers, flooring, etc. Upon selecting these items on the model you can pull up the specs associated with it, total quantities, etc. Sounds great but will take a lot of time to input every single thing along with their specs. I guess you could make a simplified model and check for conflicts but this can be done faster and cheaper with a good Q.C. check of the Construction Documents.

In our case history with Revit, it can help you create your standard 2D drawings faster, especially on the Architectural side of things. However structural we didn’t see a big payoff since most structural drawings are stick drawings with typically detail sheets. With Revit you still have to go in and call everything out so the details are not completed after the model is finished.

I’ve designed 100’s of CVS, Wal-Marts, Home Depot’s and all your typically big box retailers and this would never be more efficient then the process they use know. If you have ever been involved in the design or construction of a Wal-Mart you will quickly learn it is a highly efficient program that many other companies have copied. If it will produce a better product faster or cheaper Wal-Mart will implement it into their program. So far no BIM for Wal-Mart. On those 1 of kind projects were you already have a larger budget I could see the advantage of a full blown 3D model but I still think a good design team and final review of the entire construction documents, is better then new software.

 

[archeng59]

Steelylee, the Gehry buildings are definitely one of the types of structures where 3D modeling would be beneficial.

 

[DaveVikingPE]

BBENG,

Are you saying that tilt-up structures with metal deck on steel joist roofs don't need to be BIMmed?

If so, I would find it really hard to disagree.

I agree that the BIM should contain everything, down to just how many washers were used on the soap dispenser's wall fastening!

http://www.eatyourcad.com/tag.php?tag=BIM

has some excellent, healthy/cynical BIM discussion. I recommend it before making a "final" decision on BIM.

I see two camps: 1; the architects who see BIM as an even better paint brush to thus paint their vision on the canvas of the world, 2: the engineering firm VPs who are killing themselves worrying about how much it's all going to cost, how they're going to get around letting anyone do any creative work or (worse) really get into their projects on a team basis, and how they're going to spread liability thin enough...

 

[nutte]

A question for jeffandmike or anyone else using BIM:

Is every single structural element included in the model? I'm thinking of a steel joist/metal deck roof, which has edge angles, miscellaneous angle framing at mechanical openings, angle or light gage kickers at storefront windows and parapets, things like this. If the answer is "yes," I can see the structural engineer's time increasing a lot to get these items modeled, loaded, analyzed/designed, etc.

To echo some other people's thoughts, BIM may be great for large projects, but I'm not convinced it should be applied to the vast majority of building structures.

 

[JAE]

The message I'm hearing is that you DON'T model everything - in fact - part of the art of using BIM is to know when to quit adding things to the 3D model and complete the "drawings" in the various views (i.e. sheets) that you create.

Walter P. Moore in Houston is a firm that I know is using Revit right now - one of their engineers has spoken at an engineering conference I attended and indicated that they are having good success with it on the larger projects that they have used it on.