rough cut to flooring also.

[lynches lumber]

Didnt want to highjack the professors thread but I have the same idea except I need to put it over concrete. The concrete has a good moisture barrier under it. Needs a little patch/leveling in places. Thinking about leveling and then seal the whole floor with some type of concrete sealer before installing floor. Any suggestions on the insallation? Glue the entire floor or maybe just the tongue and grooves and let it float?

[Larry]

First you need to test your slab for moisture to make sure it is suitable for hardwood.  That's easy enough...tape down 1' square pieces of plastic in a few places around the building.  Wait a day or two than check to see if there is any moisture under the plastic.

Standard method for 3/4" hardwood is lay down 6 mil poly, than 3/4" cdx plywood.  Attach the plywood with concrete nails.  Cover with 15 pound builders felt.  Staple the T&G hardwood down.  There are a couple of minor variations that use felt and mastic in lieu of the poly.

Glue down is a method for thin hardwood.  Engineered floors have there own rules.  Don't know much about either.