Wierd missing face problems

[coolcps]

I have a few long rows of windows and when a row is pretty long, then I git a problem where it seems to cut a diaganol line and not render it. Here is a picture of it from looking behind the windows.

http://img89.exs.cx/my.php?loc=img89&image=practice00077wh.jpg

 

[MrFoofles]

looks like some kind of clipping problem... try double checking all your brushs' positions making sure they're all neat

it looks like the grass textured surface is overlapping the stone one

 

[coolcps]

The grass is not overlapping, that wall is actaully up about 3 feet from the ground, just a wierd angle. The part where you see the grass is just like it has been nodrawed and you can see through to whatever is behind.