Cork floor in Finished Attic - Old Subfloor
I recently bought a 1949 cape cod cottage, and when we ripped the hideous pink carpet off the second floor, we found asbestos tiles underneath. We had a company come in and professionally remove the tiles, but in order to get all the mastik up, they had to remove the plywood subfloor to which the tiles were attached.
Underneath the 3/8" plywood we found an OLD (probably original) wooden plank subfloor running the length of the room.
We have ordered new cork click flooring to install, but have been told we cannot (at least should not) install the cork directly over these planks, especially as they run the length of the room (the direction we want the cork floor to run). We have been told if we put down some plywood, we'd be OK to lay the cork on top of that.
Now, the question is...
1) Is this correct? All we need is a layer of plywood on top of the planks?
2) If so, how thick does it need to be? The existing subfloor is not perfectly flat, but not horrible, and is solid as a rock. Can I get away with just laying sheets of luaun? Or does it need to be thicker/stronger?
Many thanks in advance for any insight!!