Liquid Leveler?
Answers: No way will it work. Its made for a small nouns or low spot on concrete. Why is your second floor not level? its built onto of the first floor, is it height? You can jack up the house and redo the supports underneath and surrounded by the walls.
Anything else is a have passageway measure
Good Luck
No Way will it work. Liquid leveller is intensely watery and will soak into the boards which violate the purpose of the leveller and ruin your plyboards.
Lift your carpets and work your passageway around the room with a long spirit height and work out what areas are out. You may have to move up boards and examine the joists if you find any dips. You may enjoy a collapsed joist.
Also check levels of window and doors. It may be that the room is generally not plumb and as a consequence could be a visual effect (ie your floor is rank but your window is not).
depending on how big your nouns is you could lay those peel and stick tiles down, if that didnt work you could run over top of it with some type of deck to bring it up level
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