Hello. I will be installing 5/8" bamboo in a hallway and bedroom. Where the hallway ends, at the bedroom door, the joists change direction and there is about a 1/4" height difference. In other words, the bedroom subfloor is about 1/4" lower than the hall subfloor. The finish floor will obviously also change direction once it enters the bedroom, I am fine with that, but I would like to keep the heights the same and avoid any raised thresholds if at all possible. The current subfloor in the house is 5/8" ply, and I will be adding 3/4"(ply or OSB) over that, but I'm not sure what to do in the bedroom. So,

Question 1
Since I need about 1" of height to match up with the hall, what would be better, a layer of 1/4" with a layer of 3/4" on top, or 2 layers of 1/2"?


I am limited to buying my materials from Lowes. Don't ask, I just am. At the local Lowes I saw 3 different possibilities as far as subfloor/underlayment goes. The first being 23/32" Plytanium Subfloor T/G Plywood. Then there is a 23/32" Plytanium Dry-Ply plywood with some sort of moisture resistant coating. And finally Advantech OSB. I know most people recommend plywood over OSB, but the plywood I saw had considerable amounts of sizable voids along the edges, I can only imagine there are plenty of them throughout the full sheets as well. So,

Question 2
Which product should I choose. The T/G plywood with voids, or the Advantech OSB? I will be stapling 5/8" bamboo over it.

I guess, I would use to 1/2" sheets(easier to work with). #2- If I had a choice, definetly plywood.

Actually, I answered my own question as far as #1 goes. I will do 1/4" first to match the height of the sub floor in the hall, than 3/4" over it because I want 1 piece of ply going from the hall and through the door into the bed room. I don't want a seam in the sub floor there.

So, that still leaves #2.

Plywood T/G sub floor with lots of sizable voids or Advantech OSB?