Grouting a decorative rock waterfall (as in a yard pond display) isn't as simple as grouting flat tile. With flat tile, you just wipe the grout over the whole surface, then scrape and wipe it off the tile face so it remains in the spaces between the tiles. With a rock surface, though, it is difficult to remove the excess grout because of the rock shape and texture. The solution is a grout bag, which is similar to a pastry bag and allows you to target the application of the grout. Grout sealant is crucial to protect the grout from water. Does this Spark an idea?
Instructions
1. Pour 1 inch of water in the bucket. Add enough grout mix to cover it. Stir with your putty knife, adding water and grout mix, alternately. Continuing until there's enough for the project. The grout should be the consistency of cake frosting.
2. Allow the grout sit for 10 minutes. Re-stir it. Scoop the grout into the grout bag, using your putty knife.
3. Put the tip of the grout bag to one of the joints between the rocks, near the top of the waterfall wall. Squeeze the back of the bag until it begins expelling grout.
4. Pull the bag backward slowly, laying a smooth, even line of grout that fills the joint but doesn't come up over it. Do the whole surface of the wall. Let the grout sit in the lines for 10 minutes.
5. Run a damp sponge lightly over the grout, smoothing it out. Wipe any excess grout off the rock surface.
6. Allow the grout to cure for four or five days. Apply a coat of grout sealant over the grout lines, using a small paintbrush. Don't get the sealant on the rock, just on the surface of the grout. Let the sealant dry for a few hours, then apply a second coat and a third in the same manner.
Tags: your putty knife, Allow grout, excess grout, flat tile, grout lines, grout sealant, over grout