Use GGifc in Grasshopper to extract external walls and their surface area

Plug Ins Geometry Gym
1

Using the ggIFC plugin in GH. Is there a way to:

  1. extract just the external walls?
  2. extract the external and internal surfaces of the external walls and place them in two groups?
2

Hi Sofie,

I can help demonstrate how this might be achieved. But the possibility to do so does depend on where the IFC was authored from, and how rich or consistent the data is. Is it authored from Revit or another popular BIM application? Is it possible to share a sample ifc file (small and simple is fine as long as it has internal and external walls)? You can share it privately if you prefer.

Thanks,

Jon

3

Hi Sopie,

Here’s one approach in how to achieve what you describe, at least from revit.
It depends on the accuracy you need. Rather than using a wall axis and offset, a more accurate detection of internal and external surface might be to get the resulant wall geometry, and compare location of each face relative to the wall plane coordinate system.

250113 external walls.gh (25.2 KB)
250113 external and internal walls.zip (7.2 KB)

Hope this helps,

Jon