How to Lay Natural Stone Grout
- 1). Seal the surface of the stones before applying the grout to prevent the grout from discoloring the surface of the stone. Porous stone can absorb the grout, which can alter the final look of the stone. Brush the sealer onto the stones using a foam applicator, spreading an even layer of sealant over the surface. Allow the sealant two hours drying time.
- 2). Purchase an un-sanded grout formulated for your stone type. Mix the grout with water according to the manufacturer's instructions until it's the consistency of peanut butter.
- 3). Place the grout onto the stone surface and use the grout float to spread the grout across the stones into the joints between each stone. Push the grout firmly into the joints with the float, filling them completely. The un-sanded grout will spread smoothly across the surface of the stones without causing any scratches.
- 4). Use a damp sponge to wipe the surface of the stones, removing excess grout from them within 15 minutes of applying the grout. Wipe the grout lines with the sponge as well to even out the grout with the edges of the stones. Wait an additional hour and then go over the surface of the tiles a second time using a clean, lint-free cloth to remove any grout residue left by the sponge.
- 5). Wait the amount of time specified by your grout manufacturer for the grout to cure completely, this could be up to three weeks. Brush the tile and grout sealant over the grout lines to seal the grout and protect it from water penetration of staining.
