Unity 5.3.5 lightning

I’m working on a game and I’ve got some issues with lightning passing through several walls. I’m not so sure why this occurs, is it because of something with the model or is it because that’s how Unity works.

Here’s some pictures what I’m talking about:

from the outside

from the inside

lower floor
[3] http://i.imgur.com/vVu2L3e.jpg

upper floor, above the room
[4] http://i.imgur.com/xqykXvP.jpg

What’s causing the light passing through walls? Is it because of the model?

Check the shader that is attached on the mesh, perhaps it’s not using/writing to shadowmaps, so you won’t see shadows.

As mentioned, topology might be freaking out, especially when you have concave polygons. In that case your triangles might be messed up.

Also, make sure that “recieve shadows” is checked on the house mesh

This picture is typical if you have no shadows enabled, since it’s pure lambertian shading in that case (shader will highlight what’s facing the light, then shades darker anything pointing away from light).
Your floor faces towards the light, so it gets shaded.
Shadowmaps would overlay shadows on top of such areas, hiding the anomaly.