Ready for flooring! Subfloor or not?

[grantgoold]

I am ready to lay the laminate flooring. I would like opinions on rather to lay a 1/2 plywood floor down on top of the original flooring as extra strength, seal and sound barrier?

If I go with the plywood, I would lay a moister barrier between the original floor and the plywood and then the suggested barrier on top of the plywood prior to laminate. I am going with a 8mm with padded backing that I picked up from Lumber Liquidators. Beautiful stuff, easy to install and very cost effective.

Thanks for the input!!!

Grant

[Tenor]

In my case, I had a good original floor that had the tunnel covered by the PO so I decided just to put the laminate flooring on top.  Since I wasn't doing a roof raise, and I have tall friends, I wanted to keep the head room.  As for a vapor barrier, I don't know why it would hurt if you decide to add a sub floor - just be sure to use tongue and groove plywood to keep it from sagging at the joint.  I also read in this web (it is from Gypsy Journal, but I renamed it in my Favorites) http://www.gypsyjournal.net/bus_project.htm an interesting alternative to plywood for the floor.  Hope this helps!