How do you fix static meshes from glitching when combined?

I currently have 2 static meshs, 2 hall way, when i overlap them part of where they overlap it starts glitching like blinking between the 2 rapidly. Here you can see a video and before u say it i know it says i need to rebuild light which i have done now and it doesnt help for anyone who thinks it will -

Does anyone know how i can fix it which removing one of the mesh or just how i can fix it in general? Thank you in advance

Try clicking on both meshes you’d like to merge and with both selected right click one and select the option to “Merge Mesh”. On that menu, there are two check boxes near the bottom: “Replace Source Actors” and one other one i can’t remember off the top of my head. You should check both boxes.

It glitches like this because two different geometric shapes are colliding and the engine doesn’t know which one you’d like to have displaying. So it just rapidly alternates between the two.

It’s called Z fighting.

The best way to fix it is to align the meshes with the vertex snapping system so that they are never overlapping.

The thing is i want them to overlap, like if they are align and not overlapping then there is sometimes space between them which i dont want to have

If the mesh is made properly and you use vertex snapping there won’t be any space.

kk thxs for the info