26 April 2013

BIM for free

l thought BIM meant others could make use of the BIM data each of us created for our own purposes. Now it seems to mean others telling us what BIM we have to do to suit their purposes. When did this happen?
When I first starting pushing BIM one of the arguments was that besides the productivity and QA benefits others could make use of the data we put in as part of our normal processes. A benefit at no cost I argued.
But now I have trouble convincing people to take up BIM because they fear clients will start asking for extra services, expecting it for free. 
This attitude is not surprising when looking through current BIM guides and example contracts. The owner is expected to make BIM demands & deliverables.

Why not have a system where BIM data that will be produced is made explicit by each participant and everyone, not just the owner, offered it 'as is' for their own purposes?
If this is done as part of the selection process those with the best BIM capabilities will float to the top. They may even get better fees.

A by-product of this approach would reduce the importance of single Project BIM Execution Plans and "BIM Managers". Each participant does their own BIM plan setting out what they do and don't do. They refer to each other's BIM plan to see what they will get and therefore what they have available to work with. Then each can negotiate with others to change what is being provided to come to mutually beneficial arrangements. 

Surely this is a better approach to encouraging BIM take up than dictatorial demands that creates resentment rather than enthusiasm. 


But for this to happen authors (typically Architects and engineers) need to be clear about what BIM they will produce, and just as importantly what BIM they will not be producing.
And consumers of BIM (typically contractors and facility managers) need to be clear what they require to use BIM in their processes. They need an idea of the minimum they require, and the cost/benefits of "nice to have" extras.

I am constantly surprised at how rarely this happens. Design consultants marketing the benefits of BIM without specifying what they will actually provide, owners asking for BIM without even knowing what FM system the BIM data will be used for. And then there are the contractors who say we're not using BIM at all if it costs any extra, no matter what the overall project cost saving might be.

On the face of it the contractors appear to be the only honest ones. But they are throwing the baby out with the bathwater. You can get BIM for no cost.
If the design team use proper BIM software, the way it was designed to be used, useful BIM deliverables can be extracted.

There are some limitations. Information is limited to that required by the author to inform how their part of the building is to be built; design intent by the consultant team, fabrication by sub-contractors.
The other limitation is it may not be delivered in the BIM format required for down stream use.

Even with these limitation there are quantifiable benefits in using this BIM data. There may be extra costs collating this data into a usable form, and converting it into the required format. But like every other part of the construction process I would expect a cost / benefit analysis to inform what is worth doing and what is not worth doing. 

So why aren't we concentrating on how available BIM data can be used, rather than fantasizing about the missing BIM data and how it could be used?

12 April 2013

Using BIM to Shirk Responsibility

In the BIM evangelist's ideal BIM workflow, where does responsibility lie, and how it is defined? And what does the term "collaboration" actually mean in a BIM context?
I've explored collaboration before (Real Collaboration - Working with Engineers), but it is bandied about so much it deserves more thought.

As BIM workflows are taken up this issue of responsibility is a sleeping dragon. IPD is put forward as a solution, but all that really does is take the problem out of the court room into a board room, where not all players are equal (see my post Integrated Project Delivery: Bad News for Architects?).

But am I being alarmist? Is it really going to be a problem? The test is what happens in the real world - let me tell you a story . . .

You want me to do what?

There is a project, a Design & Construct (D & C) project. The first contract is for the piles that hold the building up. The piling D & C contractor has to design and build the piles (even though the project has a consultant structural engineer). Let's be clear - they are responsible for the size, location and number of piles.

The architects notionally draw the piles in their model to recognise their existence. The structural engineer puts them in their drawings with spacings and locations, based on their designed structure; where they think they should go.

The architects were asked by the head contractor to set out and dimension the piles. The project architect didn't want to do it, the structural engineer said the architect shouldn't do it, but the director in charge wanted to keep the head contractor happy.

As the contractor provided no information it was done based on the structural engineer's drawings. They were using CAD, the architects were using Revit. The architects inspected the structural engineers CAD drawing and there were some dodgy dimensions - dimension text that didn't match the measured distances. So the CAD file was ignored and the piles set out based on notes and dimensions in the CAD drawings.

The architects issued their drawing, as a CAD file, to the head contractor. A little while later they got a call from the site foreman. Why didn't their CAD file match the structural engineer's CAD file? There was one extra pile in one location, one less in another. On investigation it was found the structural engineer's note - max. 1800mm centres - was followed, but their CAD file had the piles spaced greater than that, 1823mm. In another spot they showed 3 piles with dimensions that had been faked. When the piles were laid out using these dimensions they were very close together, much closer than 1800mm, so one pile was left out. The architect who did the modelling followed the structural engineer's drawing to the letter.

When the project architect went through it with the structural engineer, they said 1823mm is fine, and that yes, they did intend to have 3 piles very close together.

Now THEY can make that call, structure is their area of expertise and their responsibility. But all the architect can do is follow their drawing, or risk a negligence suit for wilfully overriding the advice of the appropriate expert.


If you get someone to draw up the work of some one else they don't understand what they are drawing.

In BIM terms, if you expect some one other than those with the expertise to model or enter data you are likely to get incorrect or at best sub-optimal results.

But wait, there's more . . .

The head contractor has a surveyor on site. The architect was issued a survey drawing that supposedly showed the as-built location of the piles. It was a CAD file. But the piles shown matched their earlier CAD file, the incorrect one.
Did the contractor build off the incorrect CAD file or is the surveyor passing off the architect's CAD file for something they have measured on site?
As the site foreman made the architects change their drawing I suspect the latter (I haven't heard if they ever found out).


Using the work of others and passing it off as your own.

Whilst I don't get too upset about others using my efforts to line their pockets, I do have a concern about accuracy and responsibility. When using the work of others it is far too easy to not bother to check that it is correct for your purposes. There is a tendency to blame others; the contractor didn't follow the drawings, the architect drew it wrong.

And if the incorrect CAD file was used by piling contractor to build off why were they using the architect's CAD file to build from? As a D & C contractor shouldn't they have produced their own set-out drawing? It would have been easy to do, they had CAD files both from the architect and the structural engineer.


Using the work of others to shirk responsibility.

By not producing drawings under their title block there is no evidence the piling contractor made any mistakes in the design of their set-out. The only evidence is the architect's and the structural engineer's drawings. But these two parties were not responsible for the piling design. The contractor has effectively shifted their responsibility to others.

So what you say, sounds like a normal day at the office. It all about human error, nothing to do with BIM.
But it is always about human error, that's why we have contracts, a legal system and technologies like BIM, to ameliorate our human foibles. And one of our human foibles is to shift future blame (i.e. responsibility) on to others where we can.

Contractors are "killing it"

But is this story typical? What led me to write this post is a comment I read from another blog - Epic BIM. It was about another topic, the comment was put forward as an example of contractors keeping solvent by leveraging BIM. It was the way they did it that caught my attention:

" I had to work on a way to shrink my contingency. I quickly learned that I could take the CAD drawings and load them up into a data collector, which allowed us to lay out in the field 100 times faster than I had been doing, plus much more accurate. This lead into better scheduling of my equipment on site. Those two things alone made such an impact on the margins that it became a 'no turning back' point for the entire company. All this, allowed me to roll this up in my next bids, where I was killing it. "

So they are "killing it" because they are taking the work of others - their CAD files - and using them directly do their work.

Engineers must feel the pain. They are now being required to do what they previously didn't - model accurately (see my post Should Engineers model accurately?), but it is others who are reaping the profits.
Architects are used to it. Getting their own drawings back as shop drawings with the only difference being a new title block is not uncommon.

I'm not being critical of contractors earning more money by being innovative, my concern is who is perceived to be responsible. If a piece of ceiling falls and kills someone because the CAD file was missing some hanging points who is at fault? The CAD file was "incorrect", but the author of that file was not responsible for adequately supporting the ceiling, the contractor was.
What is going to happen in court? I don't know about the rest of the world, but here in Australia the legal fraternity, like most lay people, is quite ignorant of the complexity of building practice and the division of expertise and responsibility.

As I see it, the only protection we can utilize is the "use at own risk" clauses we use when issuing CAD and BIM files. Although I don't know if they will actually help when someone's life or large amounts of money are involved.

The alternative is to take responsibility for everything and associated risk and try and get paid for it.


It is unreasonable to expect one party to take responsibility for, and therefore be expert in, everything.

If the producers of BIM models take on the responsibility of the completeness, accuracy and appropriateness of their model for any future purpose they will need to be experts in absolutely everything.

It is why we have professionals, who have Professional Indemnity Insurance. Expertise is split between architect, engineers, surveyors etc., and if they make a blunder they can be sued for the damage they caused. How does this work in a BIM workflow, where everyone works "collaboratively"?

The problem is "collaboration" is poorly defined, which is an invitation for everyone to have their own definition of what it means.  I've sat in a BIM Execution Planning meeting where the Quantity Surveyor thought "collaboration" meant we, the architects, would put their costing codes into our model so they could use our model for their estimates.

A definition of "collaboration" I like is "sharing". We will freely share our data with the rest of the project team. But only on an "use at own risk" basis. Our work is suitable for defining the architectural (or engineering) design intent, nothing else. Everyone who uses our data must satisfy themselves it is suitable for their purposes, end of story.

Unless data is shared on this basis it is too risky to do so. It shuts down "collaboration". I don't see how forcing collaboration through contracts without this protection will work.
Yet I see commentators making light of this concern by invoking the "BIM must be mandated to succeed" and that it will all be fixed "once we get BIM contracts" mantras.
And in any case why are we not questioning the assumption that collaboration can only be achieved via compulsion, and not through enticement? Seems a very "anti-collaboration" approach.

Another misguided approach is to insist that a BIM Execution Plan will magically solve it without detailing how. It doesn't matter if the BIM Execution Plan says the model must "be suitable for", say FM or 4D or 5D. The reality is that architects and engineers don't have expertise in these areas, so how can they possibly deliver what is required, let alone expected?

The bottom line is no one should accept enforced collaboration through BIM contracts without safeguards to their risk and responsibilities.
Until someone comes up with a viable alternative I continue to recommend everything be issued as "use at own risk", no matter what the contract says.

Another reminder for this year's RTC Australasia conference in Auckland 16th to 18th May, where I'm presenting "BIM Execution Plans: Avoiding the Noose".