IFC interoperability

[Anonymous]

Hello All,

Thirty four pages of AC 10 vs Revit 9 discussion and no mention what-so-ever of *.ifc interoperability.

In the world of my experience, construction projects travel along a "road" that connects many players (each an inhabitant of a unique "hut" in the construction project "village").

I deeply believe that some of the focus of this lengthy discussion should involve the ability of the program (s) we use to shake hands with each other.

Riff Masteroff

[Djordje]

Riff wrote:
For sure, the *.ifc exchange is not mature. However, I do believe that it can be used RIGHT NOW. And I do believe that it should be used right now. If a project is modeled in AC10 or CS2007 with *.ifc conversion in mind, then an amazing amount of info transported.

It is definitely more than ANY file exchange today is ...

Archicad to AutoCAD - complete loss of all intelligence. Microstation - not worth the mention. Archicad to AutoCAD 3D - gazillions of polygons and what not.

In a word - unusable, prone to extreme errors and a HUGE percentage of rework.

So, however imperfect it is, it is definitely more than anything that we have now.

[Anonymous]

Hello Djordje,

You wrote: "In a word - unusable, prone to extreme errors and a HUGE percentage of rework."

Harsh words. Only partly true from my experience. My first *.ifc model import into Constructor was a structural steel model (SDS/2) from our subcontractor. At the time only CS 2005 version 1-1 had the ifc addons working. I had modeled the rest of the project in CS version PR4. The two attached images reference an examination of the models superimposed and exported into lightwave. The exports came up positioned perfectly and the geometry was impressively accurate. Graphisoft has since fixed the addon problem. Btw, I had posted about the problem in these forums. Intelligence was only partly transferred.

Since then I have transported models from Tekla and Revit into Constructor. Geometry tended to be quite accurate, intelligence transfer was partial. Lately I have been doing partial exports round trip in only CS. Sometimes the imported *.ifc file had truely impressive results, and sometimes the opposite. Only within the past week was I surprised to view the distorted geometry that others have spoken of.

I would prefer to be able to discuss particular *.ifc issues in this forum.

Riff Masteroff

[Anonymous]

Hello,

Additional attachment as follows:

Riff Masteroff

[KenMcN]

Riff wrote:
Hello Djordje,

You wrote: "In a word - unusable, prone to extreme errors and a HUGE percentage of rework."

Harsh words. Only partly true from my experience...

I would prefer to be able to discuss particular *.ifc issues in this forum.

Riff Masteroff

I think Djordie was referring to the other systems he had just mentioned, rather than IFCs.

I would like to hear more about individual's experience with IFC as I've tried it but didn't have too much luck. I'll need to go through the process again in the near future and would like to be better prepared this time. I'll keep an eye on this thread to try to get some tips...

Kenny

[Djordje]

Riff wrote:
You wrote: "In a word - unusable, prone to extreme errors and a HUGE percentage of rework."

I have referred to the current practice of mostly exchanging dumb 2D or dumb 3D, with problematic results.

Sorry if it was not clear!

[Anonymous]

I'm using IFC 2x3 export to exchange 3D data with a concrete constructor (using Allplan). I must say I'm delighted with the good results, nevertheless :

1. all custom profiles used in ArchiCAD will appear mirrored / reflected in IFC ???
2. while some roofs are wrongly translated as objects, this means that all SEO on that roof are neglected?
3...
4...

I hope to be able to discuss particular *.ifc issues in this forum with others...

[Anonymous]

IFC export...

[Anonymous]

About six months ago I exchanged files with an architecture firm in Germany. The file was a complete 3D model of a 300m2 villa made from precast concrete modules. The project was designed completely in Allplan. I could readily open it in ArchiCAD 10 with a few small mistakes. Some half-height walls did not show in plan, even though the did show in 3D. A simple "find and change properties" made them visible in plan. Even the custom designed fasteners that connected the different concrete modules came across correctly as library objects along with doors and other special objects.

IFC runs circles around A-NY-THING else with respect to intelligent 3D data exchange (more than just geometry information) in the construction industry up until now. I am excited for this may finally liberate the construction industry from the dictatorship of "that one company". This is definitely the future.

[Anonymous]

I have been doing a bit with IFC exchange between ArchiCAD & Revit lately (and will probably be doing much more soon). My preliminary observations are:

1. IFC is useful now. Not perfect, not even great, but definitely serviceable.

2. ArchiCAD does a very good job of importing IFC without any special tweaks or fancy footwork.

3. ArchiCAD while generally quite good at IFC export it has some systemic problems. For example the lack of a "ceiling" tool means most AC users make them with the floor/slab tool (with a few roofs thrown in for sloping sections). This results in the parts being exported as IFC floors.

4. Revit does very good IFC output from what I've seen so far. The trip out of Revit into ArchiCAD is very clean with most elements coming in fully editable.

5. Revit is not so good at import. If the model is too large it seems to choke on properly assigning the families (this is a bit quirky and I will be investigating further). It cares nothing for layers (not having them) so those ArchiCAD ceilings (floors) become floors. Most of the input seems to be ineditable (though I'll have to get to know Revit better before I can be sure of the true extent of this).

6. There are some strange quirks with SEOs and IFC openings, but they are not much trouble so far as I can see.

All this has been based on straight up, default settings with no special templates or property sets. There may be many fixes and improvements that can be accomplished with some customization of the process. I will be investigating these in coming months.

Has anyone out there been using any customized templates or property sets? I am also curious about direct intervention with the IFC file itself. It seems that the output could be post-processed to improve the translation value.

[Anonymous]

florian wrote:
IFC runs circles around A-NY-THING else with respect to intelligent 3D data exchange (more than just geometry information) in the construction industry up until now. I am excited for this may finally liberate the construction industry from the dictatorship of "that one company". This is definitely the future.

To paraphrase Churchill: "IFC is the worst thing we have, aside from all the others."

I agree that IFC is far and away the best means to transfer building model data that we have ever had. Of course it is arguably the only means we have ever had.

The good news is that it works pretty well and is getting better. I would like to live to see the day when the reference data structure is in the form of an IFC model server and all the other software just checks out and updates the parts it needs (ala Teamwork). This way (in principle) an Architect using ArchiCAD can work interactively with a structural engineer using Tekla, an MEP contractor using Revit Systems, and so on. All while the owner/developer and contractor (in a design-build deal) can participate in the process with an IFC model viewer.