How to Get a Stone Slate Adhered to a Block Wall

Mix up some of the thinset mortar according to the instructions on the side of the container (different-sized containers have different water requirements). Use the bucket and pour the dry mix in first. Add the water and mix it with the drill until it is creamy. Let it sit for several minutes for the chemicals in the concrete to bond with the water and re-mix.

Spread a layer of the thinset mortar onto the surface of the brick with the flat side of your notched trowel. Fill in all of the grout joint voids as well as skim coat across the entire surface of the block wall to leave a flat installation surface. Let the coat dry for 24 hours before mixing more thinset for the installation.

Lay out the wall in which you are installing the tile so you know where to start the installation. Use pieces of tile laid out on the floor to get an idea of how much distance there is between two tiles and four tiles and so forth, as this can help you determine how large the cuts will be in the corner and if you need to adjust the layout for better sized cuts.

Mark lines on the wall with a level and pencil using 2-foot intervals for horizontal lines and 4-foot intervals for vertical lines, or wherever is closest to those measurements according to the tiles laid out on the floor. These lines will intersect, creating rectangular penciled-in boxes on the wall that will guide your installation up the wall and help you keep the grout joints level and plumb.

Mix some more thinset and install the slate stone onto the wall in the mortar. Spread a layer of thinset onto the wall with the notched trowel in the lowest box you’ve drawn on the wall, and spread the thinset to the perimeter lines of your box. Press each piece of stone into the mud and work your way up from the bottom of the floor to the top of your installation area. Guide the overall level and plumb of your installation with the reference pencil lines and use tile spacers and wedges to help keep the joints uniform.