Hi @liverbird,
Thank you for your question about replacing a damaged skirting tile on your balcony.
The fact that there is a skirting tile on your balcony is a pretty good indication that there is a waterproofing membrane beneath it, so everything should be done with caution to protect this membrane as much as possible.
Start by removing the grout between the damaged tile and its neighbouring tiles using a grout removal tool such as this QEP Double-Sided Grout Removal Tool.
Once the grout has been removed, use a prybar to pull the skirting tile off the wall. You'll want to get the flat end in behind the top edge of the tile and then lever it off. You may need to use a hammer to tap it into the gap behind the tile.
Once the tile has been removed, you're going to want to remove as much tile adhesive as possible. A paint scraper or chisel would be the best option for this, as they can be controlled reasonably well, so damage to the membrane can be avoided.
You can then stick a replacement tile in place using a tile adhesive such as this Dunlop Wall Tile Adhesive. Apply the adhesive using a notched trowel, then press it in place, ensuring that the notched adhesive compresses and suctions to the wall.
You're also going to want to use some tile wedges or thin packers to ensure the tile sits up from the floor tiles; direct contact between these tiles can cause issues as the wall and floor will move in slightly different ways.
Once the tile is set, you can seal the gaps on the top and bottom edges with silicone and the gaps between the tiles on the sides with grout.
Check out How To Tile a Wall and How To Grout Wall Tiles for some further information on similar projects.
Let me know if you have any further questions.
Jacob
