Leveling an uneven bathroom floor - HELP!
No, that will not work. 1/2" ply is way too thin, the floor will feel like a trampoline. What you really need is to re-do the floor the way it was. If you wanna try it let us know and we can help you. Otherwise your method has merit.
I would make the strips narrower than 6" if the floor's slope is not consistent, maybe as narrow as 2", otherwise 6" is ok, and you will need a 3/4" t&g plywood subfloor. Also you should use 1/4" concrete backer, no need or benefit to using 1/2". Actually Ditra would be even better, and it only raises the floor 1/8" if that matters.
3/4" in 5 and a half feet is a big slope, did the house sag? Have you considered jacking the darn thing up? You will note from the above that the low side of the room will be raised about 1 3/4" with 1/4" board and the other side will be an inch higher from your present subfloor which I think is what you want.
Tile 4 You LLC Troy, MI
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