how to exclude a room from global illumination?

Hi there,
I'm trying to create a basement inside a house and I want it to be pitch black (I'll put a realtime light myself), therefore I don't want any light to illuminate the walls. I put the basement on a layer not affected by my directional light but the GI still affects it and makes it bright (I'm baking all my lights). How can I prevent that?

Thanks

 

oh, I found out the problem just now...the walls material had a bit of smoothness set (0.5) and so it was getting illuminated from the GI. Is that normal?

 

Hey, I'm trying to achieve basically exactly what you're doing. Are you able to light your basement with a realtime light even though it's baked?

 

I'm able to illuminate the walls with a realtime spotlight but my basement meshes are not included in the lightmap bake.

 

Ah okay. How did you exclude them from the lightmap? My basement is just pitch black because it receives no light, but my realtime lights have no effect on it

 

my meshes are set to static but I unchecked the "Lightmap Static" option. Also, the realtime light cast light only on my basement layer. All meshes have cast and receive shadows. Hope it helps