Leaks and "dirty" baked shadows

Please HELP! Check screenshots

I don’t understand what is wrong with my baked light or mesh. Im getting “dirty” shadows and light leaks.

My building block-out is consists of two meshes for simplisity of testing (outside and inside parts). I tried before with every room being separate mesh, but its still gave me leaks and “dirty” shadows. I using UE generated Lightmaps.

Things which i tried already:

  • Different Lightmap resolution
  • Checked index for baked UV
  • Increse baked light quality (Static Lighting Level Scale, Indirect Lighting Quality, Production Quality Bake)
  • Add Lightmass Portals on Windows and doorways
  • Changed wall thickness (now its more thicker)
  • Different export/import mesh setting

P.S. Its not like its my first time working with baked lighting, i created sceen with baked light light before and everything was fine. But its first time baking light with builiding like this