topic Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available in Collaboration with other software

Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Mikko Lahti — Fri, 30 Sep 2022 14:36:10 GMT

New legislation for applying building permit electronically mandates the use of certain custom property sets and properties in the ifc file to be submitted to the authorities. They include stuff like Site Address, Contact details, etc. The properties are mostly required in the IfcBuilding entity level, plus a few in the IfcSite. Looking into it, I was able to add them in the IFC Property Mapping dialogue, but can't assign any mapping rules to them, which means they would have to be input manually, although all of the required information is available in the model (Project Info, AC Properties, etc.) Am I missing something, or is this really the case? Screen shot below.

Using AC25.4013 FIN on Mac.

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Laszlo Nagy — Sun, 19 Jun 2022 14:19:46 GMT

Yes, this is the case. I would say it is probably because IfcSite and IfcBuilding are entities that have no equivalent element type in Archicad and Property Mapping is always based on elements in Archicad - you map the Parameter or Property of an element in Archicad to an IFC Property in the resulting IFC file.

There is a video that talks about the use of four fields (Project ID, Site ID, Building ID, Building Name) in the Project Info Dialog, and the automatic mapping of the "Building Name" field to the "Name" IFC Property of IfcBuilding. Here is the video:

https://www.youtube.com/watch?v=iVXvLcKBWBY

But that is the only mapping that is being done on the IfcSite and IfcBuilding level and it is hard-coded into Archicad. So yes, you will have to input those values manually, and besides that the only thing you can do at this point is to make a wish for this functionality, so we can submit it to Graphisoft for consideration.

If you do make a wish, please post its link in this thread.

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Miha_M — Mon, 20 Jun 2022 11:28:10 GMT

As @Laszlo Nagy explained these entities seem to be hard-coded. The Project Info - Ifc translation relation for IfcBuilding is also explained here:

IFC Data Types (Graphisoft.com)

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Mikko Lahti — Mon, 20 Jun 2022 13:27:49 GMT

Thanks @Laszlo Nagy & @Miha_M for your prompt replies.
I think I'll make a product wish for the Project Info parameters, including the custom ones, plus Location settings to be made available for the IfcSite and IfcBuilding property mapping. Much of the required information is already hardcoded into them, but sadly doesn't help since the idea here is to use the precise naming format given for the custom ifc property sets and properties, so that they can be automatically processed in the receiving end.

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Mikko Lahti — Mon, 20 Jun 2022 14:27:51 GMT

Here's the product wish link: Project Info and Location Settings available for I... - Graphisoft Community

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Kamelite — Tue, 05 Jul 2022 10:47:28 GMT

I have a similar issue; all the IFC-models in a certain project are to be uploaded to a server that puts them in the "real world" . The way this is done is by having a Propertyset with the required information in the IFC-file, and according to the person who told how they do it, the PSet has to be on Site-level. Two of the properties contains Easting and Northing... Like ML_Arco above, I discovered that you cannot assign any properties in IFCSite. So, how do I solve this?

I have contacted the person that told me this, but he hasn't answered my mail...

.Kamelite

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Erik Bjornhage — Wed, 10 May 2023 09:14:38 GMT

BUMP on this topic.

Are we any closer to a resolution as we have a similar problem.

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Kamelite — Wed, 10 May 2023 13:06:27 GMT

As I later discovered, you can actually do that, but not the way we are used to.

Here is what you do (and I have actually tested it, but I can't see any reason it won't work):

In Archicad, om the IFC-Project Manager,.and open the Site-folder:

Basically, do like you are mapping a P_Set for IFC-export: Press New, and the first time you do, you enter both P_SetName and Eastings (Or whatever you prefer). The next time you hit NEW, you make sure the P_set is the same, and enter Northings. Theese two properties have to be fed directly in the IFC-manager, like I just did in the picture.

The, close the manager, and export. No need for any work on the IFC-exporter. It is already done, since the P_Set is made in the IFC Project manager.

I eportet a little test-project to Solibri, and the result looks promising:

Of course, if your particular server requires a certain syntax, you just name the different elements accordingly.

By the way, these coordinates is in

EPSG 5110
ETRS89 NTM zone 10

If that information is required to make this work, you now know how to do it!

.Kamelite

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Erik Bjornhage — Fri, 12 May 2023 11:11:24 GMT

Very cool

Thanks for the - now comes the fun part...testing 😄

We're probably looking to input WGS84 as well as the Swedish reference coordinates.

We'll see how it goes.

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Kamelite — Sat, 13 May 2023 08:07:30 GMT

I would love it if you took the time to tell me if this solved your issue.

.Kamelite

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Erik Bjornhage — Mon, 15 May 2023 12:34:52 GMT

I will definitely let you know.

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Kamelite — Mon, 15 May 2023 15:07:06 GMT

When created directly in the IFC-manager, no further action is needed. It is mapped for export to IFC by default when created in IFC-manager.

You won't find any mapping rules because you have no actual properties to map...

.Kamelite

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Miha_M — Mon, 15 May 2023 16:27:09 GMT

Did you do any testing? What happens if you have a project location defined by the Survey Point? What happens when you add this additional Pset location data to it? How does the IFC exported model look like in terms of location? I don't have the time to test this right now...

Re: Custom ifc properties for IfcSite and ifcBuilding have no mapping rules available

Kamelite — Mon, 15 May 2023 16:47:58 GMT

I did not do any testing. But I would guess you have to choose, depending on the usage of a particular model, In my case, the models were to be used in a server that placed them on a map, based on coordinates. The server imported the IFC files using modellspace zero point as referance, so by giving that specific point coordinates, it would be possible to place the models correctly in world space.

.Kamelite