floorsqueakwood
I've purchased a home where the previous owner installed 3/4" wide plank pine over a 5/8" plywood subfloor. The plywood is glued to a concrete slab but there is no felt paper between the 2 woods. Yes – it squeaks! They wanted the character but we'd like a little less squeak.
Any ideas on what I could do to reduce (not eliminate) the squeak?
It's also known as rosin paper:
Its main purpose is to stop air leaking through cracks in the subfloor and floor which is especially important if the space below the floor is unconditioned. (You'll also find claims that it prevents the floor from squeaking or muffles sound transmission through the floor.)
You should consider doing something mosaic-y there because the size difference will always prevent you from putting in a milled transition piece.
If you try to install something that looks perfect, it will always look imperfect. But if you go with something that is intentionally imperfect, it will look intentional.
Best Answer
Since it is on a concrete slab, I don't think there is much you can do except tear it out and start over.