I got this problem when you have multiple walls intersecting each other and wish part of their faces have materials, and because of the same coordinates of the faces I’m getting weird results both in viewport and renders. One option is to move intersected wall out of the face that has the material on it but I’d like not to touch and reshape/resize their original dimensions. Any idea how to resolve this issue?
This is a common issue and goes by the name of z-fighting. Being Z the distance from the viewing point (or camera) the software can’t decide which face to show when two or more fall into the same z-distance range. AFAIK there’s no solution other than either move the face you want to be seen in the foreground, or move the other slightly backwards