Strange horizontal shadow like artifact across all the walls?

Hi,

I am trying to light an apartment and using skylight with a cubemap Hdri. After building the lighting, I am getting a strange horizontal shadow like patch across all the walls. Can some one please help me get rid of this?

Hi!

I think the problem is that ALL your lightmap resolutions are EXTREMELY low and all you get is a blurry low res result!!
…I have a short tutorial lighting up a scene using a single HDRI, it might help…