"J" wrote in message
...
From what I read, laminate flooring manufacturers want a floor within
3/16-inch across 20'. What tool can I use across a floor to determine how
level it is? A 4' level doesn't do much good.

Thanks.



I've never used this kind of thing, but here's an idea:
http://www.komar.org/projects/crawlspace/laser-level/