Help.. Trying to add a window into my wall

I cannot find this subtractive brush, that the video tutorial shows… I don’t even have a brush box tool inside my box details after I make the box, so it makes it impossiable to switch it to subtractive. I can make the wall and alt to make a new copy but neither copy has brush setting. I don’t understand what I’m supposed to do… Can someone help?

Which UE4 version do you use?

First of all try to reset all windows

After that, search for “Geometry -> Box” inside of Modes and place some boxes


Go to the Detail Panel and set the box to Substractive (make sure you are selecting the box)


Does this also remove the collision in the subtracted area?

yes it does - tested

Does this only work on additive brushes or is it possible to subtract from other meshes? Essentially I have a mesh that is an asteroid and I want to subtract from the asteroid to create an opening so I can make a cave inside the asteroid. The brush will subtract from other geometry brush objects but not my uasset static mesh asteroid. I’m in 4.12 (it must be 4.12 because it’s a specially modified source code version that will only work with 4.12). I would edit the assets in Blender but they are uassets from an unreal store package so I can’t export out of UE4.

Yes, it only works on brushes, not on static meshes.
If you want a hole in your Asteroid Mesh, you first have to export your Asset(as FBX or .obj) and import in Blender to edit it.
Here is the export option(sidenote: i convert the box brush into a static mesh - you can find the option inside the detail panel if you select your box brush):

I was under the impression it’s illegal to modify assets purchased from the Unreal Store using 3rd party software. Is that not true?

Found that here:
I hope this could help you