A couple of days ago we started tearing apart a bedroom that is going to be converted to a craft room. When we pulled up the carpet there was a plywood sub floor even though I knew there was supposed to be hardwood. They did the same dang thing in the hall, another bedroom and the ‘good living room’ that we aren’t sure what we are going to use it for yet. The joing now poker room has only the hardwood under the carpeting so we can at least selvage that room. Upon further investigation the original hardwood floor is rather nice looking in the closet so could easily be restored. My question becomes can the plywood subfloor be carefully removed in a fashion that we could restore the floors? Each sheet is nailed about every 8 inches. My second question is if we can’t restore the floors should the plywood be removed before putting another floor down.

Only way to know what the original floor will look like it to tear up the plywood and check. You’ll have to fill all the holes and then who knows what it’ll look like. If you can stain them to blend in, it might not be bad. If you’re adding another wood floor, it’s going to be pretty thick if you put it on top of the plywood. That’s going to make for a big transition from one room to the next.

There are prefinished hardwood floor putty fillers. Even after blending the colors to match, you may still be able to visually connect the dots (nail holes) from afar depending on how many holes and the diameter of the holes.

I think at every 8 inches, you will see a ton of filled holes. i’d rip up the ply and maybe the existing hardwood depending on the height/transitions. start with the plywood and bring in a few hardwood guys to give estimates/recommendations.