How to Replace Mosaic Tile on an Outdoor Firepit

Replacing mosaic tiles on an outdoor firepit requires a number of tools, materials and procedures. You'll need tools for removing the old mosaic tiles and replacing them with new ones. If you take your time with this project, you will find that the steps are doable. Your end result will be an attractive firepit that you and your family and friends can enjoy.

Mosaic tile adds a stylish touch to outdoor firepits.
  1. Remove any cracked or broken mosaic tiles from the firepit area, placing a putty knife under damaged tiles and hitting the putty knife gently with a small hammer. Chip off any remaining tile chips or old mortar, using the putty knife and hammer. Wipe off the area with sponge and water.
  2. Apply thinset mortar to the cleaned area of the firepit, using a notched trowel. Hold the notched trowel at an angle and spread the thinset onto the area in a thin layer. Make straight lines in the thinset, using the notched edge of trowel.
  3. Apply a thin layer of thinset onto the back of new mosaic tiles with a trowel. Press the mosaic tiles firmly onto the prepared firepit area, while the thinset is still wet. Wipe off any thinset on front of the tiles with sponge and let cure. Use a tile cutter to cut any tiles to the correct fit.
  4. Apply grout to the crevices of the new mosaic tiles. Spread the grout smoothly and evenly, using a grout brush. Wipe off any excess grout with a sponge. Let the grout dry completely, then apply grout sealer and let it dry before using the firepit.

Things You Will Need

  • Putty knife
  • Small hammer
  • Sponge
  • Bucket
  • Thinset mortar
  • Trowel
  • Mosaic tile
  • Mosaic tile cutter
  • Grout
  • Grout brush
  • Grout sealer


  • Wear safety glasses and heavy gloves for this project.
  • Wetting mortar before removing cracked tiles will help to keep down dust.
  • Old grout may have to be removed to reach and replace some of the broken tiles.


  • Do not use an excessive amount of water to wipe off thinset or grout on newly installed tiles.

About the Author

Barbara Freeman is a teacher and has been writing since around 1995. She's written curriculum for Discovery NutshellMath software and her NutshellMath tutorials appear on the Discovery Cosmeo homework website. She's also written for Freshfilm.com. Freeman earned a Bachelor of Arts, a credential and a Master of Arts in educational technology.

Photo Credits

  • mosaic circle image by Dumitrescu Ciprian from Fotolia.com