Lines in rendering Tweet

[robotnik]

I'm really amazed by my rendering. The file is a Autocad one converted through Sktechup. When I try a basic render I get stripes in the renderg, same with directlightin, or pmc or other. I put a basic material on the objects. Thanks for your help
What could it be

[robotnik]

I found the problem, in fact I was in a too big scale. I divided the project by 100 and everything is ok now..