I discoverd our IFC files have a separate deviation under the BaseQuantities / GrossVolume parameter:
The amount given is 1000x too large.
In Solibri the amount Volume under Quantities is correct (for example 32.001m³).
The amount GrossVolume under BaseQuantities of the same Space is 32,000.7711m³.
So far I can see everything is correct in Revit.
I can't figure out what is wrong...!
Yes we do.
I've changed it to al m and then its ok.
But isn't it possible to have the length unit set in mm and the area and volume set to m, and still get a correct IFC export?
I have the problem above too. Now it turns out that from Revit 2x a NetVolume and 2x a NetSideArea is exported. This while one of the NetVolume is actually GrossVolume and one of the NetSideArea is actually GrossSideArea.
I discoverd our IFC files have a separate deviation under the BaseQuantities / GrossVolume parameter:
The amount given is 1000x too large.
In Solibri the amount Volume under Quantities is correct (for example 32.001m³).
The amount GrossVolume under BaseQuantities of the same Space is 32,000.7711m³.
So far I can see everything is correct in Revit.
I can't figure out what is wrong...!
Last edit: Bart Jeurissen 2018-09-04
Do you have a mix of units in mm and m?
Yes we do.
I've changed it to al m and then its ok.
But isn't it possible to have the length unit set in mm and the area and volume set to m, and still get a correct IFC export?
It should be, and I thought that was fixed, so we will take a look.
Angel,
any news on this topic?
This is a known issue (REVIT-130647) that is on the list to fix. I'll give it a nudge.
I have the problem above too. Now it turns out that from Revit 2x a NetVolume and 2x a NetSideArea is exported. This while one of the NetVolume is actually GrossVolume and one of the NetSideArea is actually GrossSideArea.
The illustration shows that an IfcWall (#69366) received the following BaseQuantities from Revit.
• # 69551 = IFCQUANTITYLENGTH ('Height', $, $, 2390.);
• # 69552 = IFCQUANTITYLENGTH ('Length', $, $, 5800.);
• # 69553 = IFCQUANTITYLENGTH ('Width', $, $, 110.);
• # 69554 = IFCQUANTITYAREA ('GrossFootprintArea', $, $, 0.638000000000006);
• # 69555 = IFCQUANTITY VOLUME ('NetVolume', $, $, 1524820000.);
• # 69556 = IFCQUANTITYAREA ('NetSideArea', $, $, 13862000.);
• # 69557 = IFCQUANTITYAREA ('NetSideArea', $, $, 9.76160000000001);
• # 69558 = IFCQUANTITY VOLUME ('NetVolume', $, $, 1.07377600000001);
69555 is named NetVolume but should be GrossVolume.
69551 * 65992 * 69553 = 69555
2390 * 5800 * 110 = 1524820000
69556 is named NetSideArea but should be GrossSideArea.
69551 * 65992 = 69556
2390 * 5800 = 13862000
In addition, there is also a unity difference.
69555 is in mm3 and 69558 is in m3.
69556 is in mm2 and 69557 is in m2.
The above is a major problem at the moment because we can not work with BaseQuanties now, while the parties do assume this.
As a wall, by the way, has a curved top by a Edit Profile, no BaseQuanties are exported at all.