Install mosaic tiles

1.1.    In a high-humidity room such as a bathroom, you should install water-resistant gypsum board before tiling. In other rooms, such as the kitchen, regular drywall is sufficient. The surface must be clean, dry and even.
 
1.2.    On a painted wall, lightly sand the surface to be tiled.

1.3.    On an existing tiled wall, scrub the surface with degreasing cleaner or a solution of 50 ml hydrochloric acid in 1 litre of water. Rinse and leave to dry. Use a latex-based adhesive. 

1.4.    Switch off the power to electrical outlets.

1.5.    Protect the counter with newspaper and masking tape.

1.6.    Have a bucket of water and sponge handy.

2.1.    Snap a vertical chalk line in the centre of the area to be tiled.

2.2.    Snap a horizontal line, perpendicular to the first, to mark the position of the first row.

2.3.    Screw a ledger board between the bottom cabinets onto the wall to support the tiles.

3.1.    Using a notched trowel, spread a thin coat of tile adhesive over a small section of wall to one side of the vertical centre line. Hold the trowel at a 45o angle. Make sure that the reference lines stay visible.

3.2.    Cover an area of three to four linear feet at a time.

3.3.    Make grooves in the adhesive using the notched side of the trowel; the grooves should all be facing in the same direction.

3.4.    Dampen the adhesive if it starts to harden.

4.2.    Lay the first strip of mosaic sheet using the reference lines as a guide.

4.3.    Gently push the sheet into the adhesive to make sure it adheres to the wall. Be careful not to press down too hard or the adhesive will be squeezed up through the joints. If this happens, remove the sheet, spread out the adhesive and start again, this time pressing less hard.

4.4.    Lightly tap the tiles with a rubber mallet to make sure the sheets are firmly set on the wall.

4.5.    If necessary, cut the sheets to the right size with scissors or a utility knife.

5.1.    Install the sheets of mosaic in the first row, working from the centre of the wall outwards.

5.2.    Separate each sheet with plastic spacers to ensure even spacing. The gap between each sheet should be the same width as the gap between the individual tiles.

5.3.    Use a level to check that the tiles are flat and even. You have about twenty minutes to adjust the sheets before the adhesive hardens. 

5.4.    Lightly tap the sheets with the rubber mallet to make sure they adhere firmly to the wall.

5.5.    Cover the entire surface, section by section.

5.6.    To work around electrical outlets, position the mosaic sheet over the outlet and cut the sheet to fit around the outlet.

6.1.    Place a sheet of tile around the electrical outlet (or other obstacle), and take the necessary measurements in order to cut the tile or tiles.

6.2.    Use a wet saw to cut the mosaic tile sheets. Do not cut mosaic tiles individually with a wet saw; they are very small and you may injure yourself.

7.1.    Measure the space to be covered.

7.2.    Cut individual tiles from a sheet with scissors or a utility knife

7.3.    Remove the protective film and wet the tile.

7.4.    Cut to size with a tile nipping tool.

7.5.    Apply adhesive on the back of the tile piece and press in place.

7.6.    Repeat until the entire area is covered.

8.1.    About three hours after installing the tiles, remove the protective film from the surface of the sheets. If the sheets still move when you do this, wait a little longer. Lift one corner of the film and pull on it gently and diagonally, keeping it parallel to the tiles.

8.2.    For natural stone or matte-finish tiles, use a sponge to apply sealer thirty minutes after putting up the tiles. The sealer will prevent the grout sticking to the tile surface.

9.1.    When all the tiles have been installed, wipe off the excess adhesive with a damp sponge. 

9.2.    Wait 24-48 hours before grouting the tiles.

9.3.    Remove the spacers and dampen the mosaic with clean water.

9.4.    Mix the grout according to the manufacturer's instructions.

10.1.    Dampen the tiles with clean water before starting to apply the grout. That way, the mixture will be easier to apply and will have less tendency to stick to the surface of the tiles, which makes them easier to wipe clean afterwards.

10.2.    Mix the grout according to the manufacturer's instructions, ensuring that it is evenly coloured. The grout should have the consistency of toothpaste.

10.3.    Using a rubber grout float, work the grout into the joints. Hold the float at a 45° angle.

10.4.    Apply the grout section by section, covering a surface no bigger than 10 sq. ft. at a time. Do not apply grout to gaps separating the tiles from another type of material, a bath, a countertop or room corners. These gaps must act as expansion joints and will be sealed later.

10.5.    Use the float to remove the excess grout. 

10.6.    Clean the surface with a damp sponge, working diagonally over the tiles. Rinse the sponge often, using as little water as possible so as not to dilute the grout.

10.7.    After 24 hours, when the grout is completely dry, apply grout sealer to the joints.

11.1.    After about ten days, caulk the expansion joints with silicone sealer.

11.2.    When the silicone is dry, clean the tiles with a soft, dry cloth.