Before grouting, the tile joints must be cleaned of all adhesive residue to a depth equal to two-thirds the thickness of the tile. Ideally, excess adhesive should be removed while it is still soft. If the adhesive has hardened, use a narrow tuck-pointing trowel, a utility knife, or a scraper to pare down any excess (see Figure 1).
Figure 1. Patches of excess adhesive buildup in the joints can cause splotches on the surface of colored grout. If the adhesive hardens before it can be removed, cut away any excess with a tuck-pointing trowel or scraper to a depth of two-thirds the tile thickness. This is particularly important when applying colored grouts, since variations in...
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