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SWEETS IS ONLY SUPPORTING BIM FOR REVIT


JohnS

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Civil design is important, but not something an architect should or should be required to do, except in very small and simple projects.

The BIM-concept that eg. IFC is based on makes, in my interpretation, quite a few (valid) assumptions:

i single, one-off ?long timber?* residences and McMansions are not even near the focus.

ii there are specialist consultants.

iii the specialist consultants get the geometry (eg. terrain, but more importantly spaces, columns, beams, slabs and the like) from the Architect and in principle only add information to the Architect's objects.

Ad-hoc, my-way BIMs are another pot of chickpeas.

EDIT

*) This expression is used in the Nordic countries to describe the ancient way of construction demonstrated so eminently by the framing tools of VW. No-one but the DIY-builder builds like that here: we have prefabricated elements.

Edited by Kool Aid
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I agree that your assumptions are valid, at least for some models of practice.

The issue here is, "how is BIM management monetized?"

Architects compete for private sector jobs based in part on fees, and public sector fee curves have not generally been adjusted in order to compensate the architect for BIM management.

And our traditional model is an arm's length relationship between the Architect and Builder.

Requiring the architect to be responsible for the accuracy of quantity surveying, is problematic from a liability standpoint under traditional practice.

By and large BIM has to pay for itself on the design side or be an Owner requirement.

And when it's an Owner requirement, there are likely to be legal issues beyond those adressed in standard contracts.

Edited by brudgers
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And I mainly agree with your notions!

The comprehensive model -approach does indeed have various cost implications that cannot be ignored. These include the obvious changes in the project-wide workflow between the disciplines, esp. between the architect and the structural engineer. Depending on the client-side implementation, we may need to eg. have each and every column and beam not only modeled but also uniquely and persistently identified.

Management of the design model in course of the project is a definite issue in many ways. This aspect is a threat to us VW-users: I don't see any signs of supporting server-type of solutions with a shared database.

But who cares: in the absence of IFC-certification, VW can't be used in IFC-based projects for discerning clients anyway.

As comes to quantities, the legal responsibility does not really, fundamentally change. We've always been responsible of the correctness of our drawings and schedules. If anything, the brave new approach helps in this respect, especially regarding discrepancies (my fav red-face-in-the-site-meeting -issue.)

Finally, I feel very sorry for the smaller construction companies that will be out of business because they don't have the resources to implement tendering based only on models. No wonder the BIM/IFC -issue has been championed in the Nordic countries by the large construction companies? And large design practices!

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Here, the architect traditionally has not been responsible for the quantities of materials, and the contractor is responsible for anything which can be reasonably inferred from the drawings.

Our architectural drawings communicate design intent.

Having one's database do so is another matter.

Particularly given our legal climate.

Suppose I have a record attached to a door symbol, and the default value for the cost field is $0.00.

I won't put cost in my printed documents, but it could easily appear in a BIM model (or CAD file).

How do I tell the contractor that they cannot rely on that information?

Particularly if I don't realize it's there?

There are many aspects of US practice which don't translate.

Liability is one of them.

Digital data approaches the boundary between services and products.

I am insured against defects in services, but not products - and I could not afford such insurance.

My drawings - printed and PDF - remain my instruments of service.

I provide CAD files and similar data to anyone other than my consultants "for convenience only and without any warranty whatsoever with the sole exception that I am the copyright holder."

When previously I worked in an environment where documents were shared between parties, it was a proprietary solution (Buzzsaw).

Edited by brudgers
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Here dimensioned drawings, schedules and specification have always constituded an implied Bill of Quantities.

Our architectural drawings communicate design intent.

You've got it easy, mate! So, it's just pretty pictures you need to do? Fancy that?

And you still call yourselves Architects? Well, whatever.

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It's not just pretty pictures.

But, means and methods of construction are the responsibility of the Builder not the architect.

That's not to say that the architect doesn't need to clearly understand the way in which construction will proceed, but that the architect cannot require that it proceed one way or another.

It all comes back to litigation, the architectural profession's lack of political power, and anti-trust legislation.

The result is that the architect is only really responsible for determining if the construction conforms with the contract documents when it is completed.

Assuming of course that the Owner is even interested in the architect making such a determination and actually contracts the architect to do so.

Sometimes, the drawings turn out to be only suggestions.

Edited by brudgers
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Same for quantities.

For example, It is not unusual to schedule doors by type.

For example, type 8 may be an office door. The hardware requirements are all the same as are the slab size and the frame.

And that common information is in the schedule.

All the doors are shown in the plans, but the schedule doesn't provide a quantity (nor does it distinguish between left/right and reverse opening).

It's the contractor's responsibilty to provide what's on the plans.

I'm not responsible if too many or too few doors or the wrong doors show up on the site, nor should I be (so long as the information to determine the quantity is in the documents).

Edited by brudgers
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I carry personal liability for 10-13 years (depending on the state and it's statute of repose).

In some states there is non statute of repose...basically liablity for architectural errors and ommissions until you die.

Though contractual liability can be limited in many jurisdictions by incorporation or similar operating entities, the architect who seals the plans remains unshielded for architectural errors.

Except of course insofar as such errors are insurable and actually insured.

And action beyond the normal standard of care is neither.

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It really depends on the type of contract being used doesn?t it?

Here in the UK currently, at least in the social housing sector, it?s strictly Design and Build, which loads all the risk and responsibility onto the contractor, and the architect?s documentation is all about design intent.

In New Zealand, a few years back now, when I was involved in private housing, we used the more traditional contract (Design Bid and Build) whereby the architect designed and scheduled everything down to the last detail. The risk here was generally shared between architect and contractor and subcontractors.

In Design and Build the architect doesn?t conduct site visits to monitor the owner?s interests. The architect is basically an employee of the contractor, and is responsible only for ensuring the design actually works.

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In Design and Build the architect doesn?t conduct site visits to monitor the owner?s interests. The architect is basically an employee of the contractor, and is responsible only for ensuring the design actually works.

Well, even that depends. Here, the local arm of one of the largest construction companies in the world, Skanska, specifically requires the architect to have an IFC-model pretty much from day one in their D&B -projects, in order to control costs, supply, timeline etc. No IFC, no job.

I suspect that Skanska uses the Land of Sanity Clause as a testing ground, since Finnish architects are required to have IFC-models in state government (and larger cities) projects. By the look of things, VW is not likely to be an accepted CAD-program for Skanska anywhere in the world.

EDIT

Potentially interesting to the handful of VW users residing in the USA:

Skanska was ranked the 10th largest contractor in the world in 2008[7] and was the 6th largest contractor in the United States.[8]

http://en.wikipedia.org/wiki/Skanska

With it's fine (lack of) action, NNA has soon excluded even its American users from D&B jobs of Skanska! Well done!

Edited by Kool Aid
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Indeed, BIM and D&B certainly aren't mutually exclusive. Integrated Project Delivery is what they call it in the U.S. I believe.

I'm really interested to see how BIM affects D&B contracts. Unfortunately it looks like this backwards industry is making the same mistakes it made when it adopted DWG as the standard, so it may be a while before I get to find out.

So which BIM software packages are producing IFC files that Skanska is happy with?

Edited by Christiaan
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I'm really interested to see how BIM affects D&B contracts.

So am I. Potentially it could be a nice additional earner of bread and butter for architects.

So which BIM software packages are producing IFC files that Skanska is happy with?

ArchiCAD is their favourite (& in-house) program, but Revit, Bentley and AutoCAD are accepted, too. Technically anything that passes the Solibri test, but I understand that they want to see the Certificate to consider other software.

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Theoretically it should not matter, but an IFC object, when imported, does generally not have parameters that the receiving program could access.

Also there are geometric conversion problems: in some cases the IFC model fails (ie. is blown to pieces) and clients who have a system, do not want to be bothered with problems or idiosyncracies.

Finally, many of NNA's tools do not generate valid alphanumeric IFC-data. In fact, the other way around: few do.

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In New Zealand, a few years back now, when I was involved in private housing, we used the more traditional contract (Design Bid and Build) whereby the architect designed and scheduled everything down to the last detail. The risk here was generally shared between architect and contractor and subcontractors.

I think this risk sharing is a bit of a conceptual misconstruction and the architect is unduly made a part of it. If the quantities provided by the architect eg. in what we here call the Proprietor's Bill of Quantities are not grossly or negligently wrong, no-one actually loses money, if variation conditions are sensible.

The definite advantage of the PBoQ is that all tenders are based on the same quantities and the winning tenderer has the best price & quality delivery. Should the quantities vary (within reason & acceptable error margin), there's no reason to assume that the winner would not have been the winner in any case. The building, unfortunately, costs what it costs.

If anything, the method (whoops: you have one!) reduces the risk of the contractor and subbies. Thus, they can price without the risk factor; ergo, the cost is lower. Enter useful BIM tools and you can reduce the error margin even more.

Variations are a pain and many a contractor makes his or her profit largely from those. When the contractor wins a job, it is finally the time for the estimators to earn their livelihood. The poor souls: when the firm does not win a job, they're blamed, vilified and mocked for overestimating; when it does, they're hanged, drawn and quartered for underestimating.

Underestimating what? Yes, mate: quantities!

But I digress?

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Digression, part 2

The incompetent would-be architects, who can't tell whether a door is left- or right-handed, may well feel clever and superior when the contractor has to make a loss because he or she has not been able to correctly interpret the Design Intent from pretty pictures. The one-off proprietor is likely to believe that his or her Chosen Architect has saved money.

Nothing could be further from truth. The loss is factored into every tender of every project.

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Skanska was ranked the 10th largest contractor in the world in 2008[7] and was the 6th largest contractor in the United States.[8]

http://en.wikipedia.org/wiki/Skanska

With it's fine (lack of) action, NNA has soon excluded even its American users from D&B jobs of Skanska! Well done!

The legal environment affects them too. Design Build is problematic for public entities in many US jurisdictions.

Few U.S. Vectorworks Only firms are doing projects on a scale where Skanska would be hiring them for a Design Build project, and much of Skanska's US work has traditionally been negotiated bid, CM, or hard bid anyway.

There just aren't that many US Vectorworks firms of sufficient scale and portfolio to chase that level of Contractor as a client...particularly if the firms have unproductive tribal allegiances.

Edited by brudgers
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Indeed, BIM and D&B certainly aren't mutually exclusive. Integrated Project Delivery is what they call it in the U.S. I believe.

Integrated project deleivery is just today's "partnering."

It's a set of processes and contractual structures (social technology) not computer technology.

Data sharing is part of it, but it's not design build by any means.

Basically, it's the AIA's attempt to move the architect more toward the center of the process - a return to the mythical time of all good.

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I very much enjoy reading these threads that seem to grow a life all there own. I am just glad the whole McMansion thing didn't start up again.

My 2 cents

A well thought out (not just pretty) set of drawings are a form of communication between the designer, owner and builder and can save many headaches and litigation.

Often the client hires the designer/architect to design a project based on program and budget. The CDs are then passed around to builders for estimates. The client picks the one that fits the budget and construction begins. The lack of detail, and forethought in the drawings along with the lack of communication between architect and builder generates changes and extra cost. The client is over budget and starts suing everyone in sight. Regardless who is responsible.

Many of the problems discussed could be eliminated if the disconnect between builder and designer was removed. Back to the days when designers were on site.

BIM design is one step closer and VW does a pretty good job of it.

I am not to optimistic about any kind of IFC standard being established. We can't even get our measuring system standardized.

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Indeed, BIM and D&B certainly aren't mutually exclusive. Integrated Project Delivery is what they call it in the U.S. I believe.

Integrated project deleivery is just today's "partnering."

Yes. Partners are expected to be able to dimension and schedule. You have very clearly told that you can't.

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Digression, part 2

The incompetent would-be architects, who can't tell whether a door is left- or right-handed, may well feel clever and superior when the contractor has to make a loss because he or she has not been able to correctly interpret the Design Intent from pretty pictures. The one-off proprietor is likely to believe that his or her Chosen Architect has saved money.

Nothing could be further from truth. The loss is factored into every tender of every project.

Repeating information leads to errors.

Calling out a door as left hand reverse opening on the schedule doesn't have any benefit.

Mira los planos!

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Digression, part 2

The incompetent would-be architects, who can't tell whether a door is left- or right-handed, may well feel clever and superior when the contractor has to make a loss because he or she has not been able to correctly interpret the Design Intent from pretty pictures. The one-off proprietor is likely to believe that his or her Chosen Architect has saved money.

Nothing could be further from truth. The loss is factored into every tender of every project.

Repeating information leads to errors.

Calling out a door as left hand reverse opening on the schedule doesn't have any benefit.

Mira los planos!

What can one say? A decent BIM tool knows what eg. a door is like to the minute detail. The NNA door does not, but it is an Integrated Product by NNA and, by definition, totally useless.

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