In article , Paul S. Brown writes
Laminate flooring is essentially faced MDF. We had a leak under the floor in our shower room (actually at the bottom of the cistern, so that it ran down the outside of the pipe, and under the flooring, *above* the membrane). The boards swelled, warped and looked generally horrid, but I fixed the leak and over the last six months they've gone back to normal. If you'd seen it at it's worst, you'd never believe that much warpage was reversible.
I guess if you painted or varnished the underside of water-resistant laminate flooring (and the edges!) that would work as well as 'basic MDF).
Regards,
Simonm.