How to Tile a Shower Base & Keep the Slope

Complete construction of the mortar bed, if this has not been done. The mortar bed should be of an even thickness so the slope that was established in the pre-pan remains. Adjust the drain strainer piece before the mortar bed is placed to reflect the thickness of the planned mortar bed plus the thickness of the tiles. Measure the distance up the walls and mark a point to indicate the mortar bed thickness and a second point above the first to mark the thickness of the mortar bed plus the tile.

Prepare the thin-set mortar for the scratch coat that the tiles are pressed into. Add a latex additive rather than water to the thin-set mortar mix and let it "slake," or rest, for about 10 minutes.

Spread a thin layer of thin set over the mortar bed. While smaller shower floor may be mortared and tiled all at once, larger showers may require division into multiple sections to complete.

Apply an additional thin layer of thin-set mortar before the earlier coat dries. Use the notched trowel, held at a 45-degree angle, to make furrows in the thin-set. When spreading the thin-set, press down hard enough with the notched trowel to make a scraping sound. The mortar should be of uniform thickness.

Press the first tile into the thin-set mortar. Use spread fingers to press down evenly on the tile and wiggle it slightly to ensure a secure bond.

Guide the remainder of the first row and check subsequent rows regularly with a straightedge, level or other suitable tool. Use tile spacers placed between tiles to create uniform spaces.

Tile the rest of the floor. Apply each subsequent tile in the same manner as the first. Press down evenly on each tile to eliminate any unevenness between tiles. Check regularly and press down on any tiles to force them to become even with the surrounding tiles. Use the level regularly to make sure that the slope remains, holding the level with one end at the line drawn on the wall and the other at the drain. Adjust the tiles as needed before the mortar dries, securing them in place. As long as there is no unevenness and the level shows that there is a slope towards the drain, the tile layer is reflecting the slope established by the underlying pan or pre-pan.