Thinset is the type of mortar that is used to install tiles. When a lot of thinset is present, such as when a substrate is not level and the thinset is used to compensate, this excess often splatters or smears onto the adjacent tile surfaces. Mortar will stick to the front of tiles easily, so the tiler will often rough wipe off the mortar. Removing the rest of the haze is not difficult if the tiler attends to it promptly.
Things You'll Need
Straight slot screwdriver
Sponge with green scrubber pad
Bucket of water
Grout haze cleanser
Remove mortar from the grout lines between each tile the same day that you set the tile. At this point, the mortar is still fresh and can be removed easily by dragging a narrow flat-tip screwdriver along the grout line. The objective is to make sure the grout line is open at least 50 percent of the thickness of the tile.
Remove spacers to clean the grout line and use the opportunity to wipe and clean excess thinset off the tile. Usually if mortar is high in the grout line, it also is on the tiles on both sides. Spacers often are covered in mortar from the rush of installation. Wash the spacer and replace it if the mortar still is soft.
Clean the face of the tile by using a small sponge with a green scrubber back. In most cases, the moisture of the sponge is sufficient to loosen hardening mortar. Wipe toward the center of the tile so that you don't pick up additional mortar passing over grout lines. Rinse the sponge frequently and clean the same tile until no more mortar is visible.
Wipe along the edges of the tile using the edge of the sponge to clean mortar off the tile edges. This can be particularly tricky if the tile is rough-edged or porous. Clean off all visible mortar on the face of the tiles and in the grout lines. Check each tile. If you leave mortar on the face of a tile, it can be very difficult to remove later. Use the green scrubber on spots where the moisture isn't enough to move the mortar.
Clean persistent mortar haze after the tiling is finished by using a grout haze cleanser. This often is a mixture that contains sulfamic or phosphoric acid. Follow the label directions for using the specific product you purchase.
Apply a steamer over hazy tile for 30 seconds. Rub the tile using an eraser-type cleaning pad. Buff the tile with a chamois. Other tools used to remove mortar from grout lines are chisels and grout line tools. Pre-seal rough or porous tiles before grouting to make removing surface grout easier.