What's BIM ... ... continued

That's why such topic is tricky: I was asked to write a "simplified" version of yesterday's. OK, never mind!


Building Information Model, in essence, is a technology platform upon which professional from AEC (architecture, engineering and construction) industry could work and share data collaboratively and efficiently.

It starts with a computerized 3D model of the subject building itself. Throwing away the legacy concept of 2D paper drawings, designers will no longer "draw" plans and elevations, but to build up a 3D model straight away in computer. 2D drawings are only flattened representation of the 3D model automatically generated by computers.

There are many advantages of using 3D model right from the start. Architects and building owners could appreciate the design visually in computer to foster confidence of the final outcome. Engineers can do analysis and design using computerized methods that usually require 3D models to base on. Last but not least, adding attributes to the 3D model, quantity sheets of building materials can be generated by computer to assist QS in tender preparation. With BIM as the common language, various design team consultants can fulfill their specific task coherently and consistently.

Design tasks will not stop when building projects enter construction stage. Contractor's proposal, design-and-build items, provisional items, detail design of specific building component, choice of propriety products, to name just a few, are the reasons why BIM is useful to contractors in the way designers do during design stages. Moreover, adding time and resource data into BIM, contractors can simulate construction activities inside computers to testify the workability and/or streamline the production processes. By shifting the try-and-error process from construction site to virtual environment, project risks, and hence a lot of money, could be saved which at the same time, help saving our environment by reducing unnecessary waste.

When the building is ready to handover to its owner/operators, the BIM will become a total digital replicate of the building itself. Today's technology allows us to link any intelligent contents, say maintenance log-book or manufacturer's web-site, into BIM to faclitate the operation of the building. It enhance facility managers to retrieve building information effectively and at the same time migrate their practices to a computerized and integrated platform.

While fulfilling its functions in design, construction and operation stages of a building, BIM could be cited as a building-life-cycle managemet tool. This is the vision that today's AEC professional opt for in the coming information-intelligent era.


Well, sounds more legible? I'm not so sure ... ...

What's BIM

Never imagine to write such a tricky topic. Just today my boss asked me to write it down I guess it's time to share my understanding of it.

Building Information Model, in general, is a data management tool, specialized in building-life-cycle data management.

The word "Model" have different intrepretation. One very common is: "3D-model with embedded data about anything of a building".

In broader sense, "Model" have speaking term with "Methodology". In this domain, BIM would mean "a Specialized Method in managing Building Information". The database so described will not necessary follow the "real-form" of a building (i.e. 10 storey building = 10 folders of file containing 3D-model and related data), but be anything that will facilitate the management of data about a building. You can imagine a magical drawing rack which will throw you the precise information about anything of a building upon your verbal request.

To give another example, in a set tender documents, the tender drawings is a kind of BIM; while the specification book will be another, though both are old-fashioned and deficient. A good BIM should encapsulate the capability of both, in addition to other intelligent contents: e.g. maintenance log-book, hyperlink to manufacturer's web site, a video of presentation by the architect.

All in all, the form of BIM, today, usually come with the former case: a 3D model with embedded or intelligently-linked data. Just bear in mind that there are other possibilies than this.

knowledge security

BIM post a big threat to authors.  Yes, it is true if the database itself is not properly managed.
 
But this seems true too for paper-means communication.  People panic with the security issue of IT side more just because they have little knowledge about how the data were manipulated inside the mahcines and through the wires.
 
Drop the hardcore hacker cases first.  Today many of the advance CAD-based software builders have developed a second data type for sharing purposes.  These light-weight format vs. propriety format help protect the geunie knowledge and methodologies about how the contents were built.  Usually they only contain essential data enough for the down-stream user ( e.g. contractor) to do their own work.  A very common example is DWF developed by Autodesk.
 
Some people refer such technology to pdf format of acrobat reader.  I would say they are far more "safe" in terms of intellectual property security.  pdf format are about graphic and text, which could be easily transformed to other formats by making screenshot and text recognition softwares (many of them bundled with scanners you buy), or simply decoded by ametuer hackers.
 
In graphical world, potable format files only contain approximate data accuracy (e.g. 0.1mm) - for example, 2 lines are seen joined in a potable format are actually broken lines.  Such low-feidility data technology reduce the file size and hinder the data reusability at the same.  Design-wise, rule-based or knowledge-based features were also thrown away - for example, the depth-span ratio of a steel beam is optimized for a designer-style staircase.  This render the digital data dispatched similar to those in legacy paper era - not better, not worser.
 
But this is only part of the story, since you have to make sure the data you shared and forming part of BIM is good for the purposes of the whole project team, there are many good chances that they conflict your security policy.
 
We'll discuss this issue later.

More on Details

People have knowledge about building and BIM would tell you to draw necessary details enough for general purposes of BIM.  Their reason: "value".  So, it's a waste of resources to hire a crew to draw the anchor bolts of a kitchen cabinet.  Also there're other reasons like software/hardware performance, data query and analysis performance, capacity of machines ....etc.

While it's too ture to argue on this issue, our mind become too solid to take a further step or just to put a fullstop at the current prospectus of BIM.

But just ask one question: are there eventually any drawings showing the hanging bolts supporting the kitchen cabinet at the end of the day?  Surely it's "yes" - not only the fabricator, but also the project engineer have to approve it's structural adequacy based on the drawing duly prepared!

There must be  "advantages" to put any data about a building into a BIM, where they appear and are referred to during a building life cycle for some time.

This is the axiom of BIM!

What we should have asked is "if we make effort to include them in BIM, is there a positive value generated?"

That's why we have a balancing point about what to/not to build in BIM.  So currently, we wouldn't expect to see an 3D anchor bolt in a BIM.

But the "balancing point" itself is not the axiom! 

That is, it's existence and position is not always true.  It should be moved or even vanished when BIM technology keep advancing so that we take lesser and lesser effort to put more and more details inside a centralized database.

The future of BIM is not hard to imagine, because it's fairy clear that we don't need the chemical equation of a waterproof membrane to appear in a building project.

Details

I went through a few occasions briefing practitioners about BIM. There's a common "phenomena" I noticed from their understanding: - "Well, we've to push the design development to earlier stages with these tools", and "our practice should make change to accomodate this advance technology" ... This "understanding" is more deepened if they "tasted" the softwares by themselves.

As I've addressed before in "Objects, Domain Objects....": in principle there's no hassle to change our process to suit particular tool if you find no justification at all.

Subject to blame: Objects. Yes, objects again - the god and devil in one body.

People start "tasting" BIM by playing with the domain objects: walls, slabs, windows, doors, stairs ... mostly. Relevant or irrelevant they also found many details of the objects they didn't expect to think of during design stages (which they assumed when playing) e.g. finish thickness, stair nosing or railing styles.

Consequently they regard the details as a "must consideration", concluding that the "details" should be taken care of at earlier stages.

My suggestion: Master your process before master the softwares.

If it's your thinking that it's a waste of time to take care of certain detail at certain stages of design, you should look deeper into the software and ask: "How?"

Generally there are 2 approaches:

1. Modify the object's parametric template to delete the unneccessary details

2. Leave them alone as "dummies". These "dummies" could be a reminder to alert your colleagues to take care of them at later stages, or as a "backup" in case you run out of time to finish them up.

If you take the second approach I will assume that you have a organized strategy to document your design processes. You may also ask how to differentiate the "dummies" from "true details". I suggest to use the 4th syntax of a 3D model i.e. color, material, transparency, etc. Take a good look into the softwares and you should find these object properties.

Draw, modify, coordinate, schedule

Whatever you will do modeling a building, especially build up a BIM, every elements should go through these 4 steps.

To draw is the easiest and toughest task. It's very easy to build anything in 3D you want. But to make it a reasonably easy object for the following 3 steps - modify, coordinate, schedule, is a kind of state-of-art.

To use the pre-packed libraries comes with the BIM softwares will help you through this. However, if that's a 3-dimensinoal hyperbolic skylight in your mind, then you must prepared to spare more time on this "draw" step. The best way is to go through all the 4 step as trial run to make sure your home-brew object is good enough.

But life is not like that. There are cases you have to change objects you made to an extent that you have to make a new one to replace it. Check the software and your drawing convention that you could do that revert/remake in a non-painstaking way.

As an example I give here the least possible trade of building elements in the world a designer would like to coordinate (or even to get a peek) - "builder's work" shown in a CBWD (combined builder's work drawing). Yes, a hole in a wall/slab for a pipe to go through! But they mean money to builder if they're not coordinated.

But I was told to schedule them out from a tower BIM into excel sheet!!



Like everybody I was scared with this idea. Instead of blaming the guy who ask the question so late (BIM was built and modified for almost a year), I turn my full attention to the software function to see if this could happen with minimal working hours.

Luckily I found that there's a feature of the software to put the results of a "measure" command into an object, like doors or windows. Eventually I can schedule out these "measure objects". What my draftmen have to do is:

- convert all "void" geometries (objects that making up the holes in walls) back to positive solids. It's a one step procedure for a whole floor. That means a 70 steps for a 70-storey high tower

- 2 "measure" commands for each discrete solid, so we could have the surface area and depth of each particular builder's work. It's painstaking but it's routine. 2 working days were spent for the first 15 floors. (including learning curve)



In the end, I spent half the time of traditional method (use calculator and CBWD hardcopy) to come up with the schedule, with the outcome could be reused for other revisions. Also, it's about 1/5 of time to reorganize the BIM to schedule out the works in normal way.

Conclusion : life is different from theory, but they all start with theory.

Automation, Collaboration, Consistency, Solver

BIM come with many advantages over our traditional methods of doing things - from inception, design, contracting, construction and facility management.

People come to you to describing the capabilities of BIM by explain the features of BIM - coherent database, parametric modeling, collaborative client-server strategies, bundled libraries, popular data formats, allied partner softwares/solutions, work scheduling tools, seamless diagnosis applications ... etc.

At first instance you may map the above BIM features/software features to your particular business processes.  Instead I would suggest you first look into the nature of these improvements if they are your/your company's concern, in terms of cost saving and quality assurance:

1. Automation
What are the value generated if particular human process was replaced/improved by putting it into machines?  Is there any balance you will strike for Quality vs. Time vs. Cost?  What and where is the learning curve?  Is there any new loopholes generated by eliminating the old loopholes?

2. Collaboration
Is quality collaboration crucial to your business?  Differentiate them from in-house collaboration to external collaboration and treat them separately.  You will probably get a 100% "yes" from your boss to both streams because it's a standard PR answer.  I assure you it's not quite so if you put this issue in monetary terms.

3. Consistency
Practically we never get 100 out of 100 marks offering our services.  One of the major reasons is work consistency - drawings, specification, illustrations and even site works.  Is "consistency" giving you a competitive edge of your service?  Give it a measure and balance it with your input to achieve it.

4. Solver
Works could be very complex that you have to put more people, and hence, money to work it out.  In extremity you may report to your boss that it's just not feasible at all to place tender on certain works.  Today's softwares open you new opportunities to tackle complex jobs and render them "feasible".  Have a good study of them to "level up" your company's profile in faster pace.


Once you categorize your improvements in these 4 fields of application, you could review it easily with the same language.  Avoid making matrix tables of evaluation for sake of global understanding.