If a wall is warped or bowed, the shelf will stand away from the wall.
How To Tile A Wall That Is Uneven. How do i prepare that for tiling. And how he can lay tile on a wall that isn't flat.
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If you're tiling over an uneven section of wall, the corners of the tiles may stick out slightly from the rest of the tiles; Cut a wooden batten so it's just longer than half the wall you're tiling. If a wall is warped or bowed, the shelf will stand away from the wall.
They can make it fit perfectly.
Tear out the entire wall (about 6 feet across) and shim the studs then rehang dry wall that is level. As for the floor being out i would pick a comfortable height (the lower the better) and establish a level line and back lay the tile to the floor but i would not do that if you are. Installing wall tile is basically the same procedure as installing floor tile. The line drawn on the shelf reflects the unevenness of the wall, and the cut you make will also be uneven, allowing you to match the shelf to.