This is an interesting subject because for once, the cheaper, thinner products that look the same as the more expensive, thicker products can actually be better.
Here's what I did with my tradewind:
I laid HOUSE WRAP over the frame and put the new floor on that. I treated the whole floor, and double-sealed the edges. I then put HOUSE WRAP on top of the floor, and laid the IKEA click flooring. I weighed the packs, so I knew the flooring weight contribution. I did not glue or pin it, and left a smaller 1/4" gap all round.
It's held up really well, and it will take many years before the house wrap degrades enough for water to even start touching the wood - at which point the wood treatments will start working