Be sure you double check the fit with the paper backing still on.
Tile over basement wall.
For tiling over tiles in bathroom walls you ll need to set up sheets of waterproof membrane in between the concrete wall and tiles.
Subtract 1 4 inch from that measurement to get the necessary tile size.
Measure the distance from the edge of the wall to the edge of the last full sized tile installed on the row.
Ventilate and dehumidify the area before during and after the installation because basement walls are usually susceptible to moisture.
Place a second uncut tile over top of the open space overlapping the tile you just placed below make sure it is flush with the wall then use the bottom to mark the tile beneath.
Now use shears to cut where you marked and you ll have the perfect size piece for that opening.