So I’ve tried enabling Use Two Sided Lighting, Enabling shadows on my sun, rebuilding the lighting, making the BSPs thicker, but nothing, to the extent of my knowledge seems to resolve this. The room should, in theory, be blacked out. Could it be because I’ve used multiple BSPs pieced together or something to do with my lighting? Some help would be greatly appreciated! The picture below is what I’m seeing.
What is your lighting set up? Are you using a Directional Light and others? Need little more info cause a couple things can cause light bleed.
Considering some objects are black there actually might not be any light leaking at all. Are you sure you aren’t just seeing reflections from sources outside the room?
Do you maybe have a large reflection capture (or skylight) outside the room that also covers this room? If so you might want to add a smaller one specifically to this room to mask out the incorrect reflections.
If you have a skylight, try deleting it.
You were right Arnage and darthviper107, I had a skylight outside of the room that I forgot about. I just added skylight to the room and that fixed the problem!