not sure that makes any sense,,, can you post a picture of the radiant brushes..maybe create just a wall and a floor and post it here

I use terrain patches, and the wall brushes go completely through them, so that's not it.

try moving the light away from the wall and try adjusting the radius. Also try changing the brightness of the light.

hhmmmm... i will have to look at that some more. it would be interesting if fixing the problem was that easy. but sometimes you get light leaking through in a place where you can't make the wall go below a floor. on my map, the light is leaking through the wall and ceiling. but i will look to see if i can change it up to see how it affects the light

here is the solution posed by the other people that posted, in picture form.

yes, that's the method i was talking about