Mosaic can be made from a wide variety of materials, the most common of which are glass, porcelain and glazed ceramic. There are mosaic types for virtually any application all offering the distinctive texture and visual appeal unique to this type of covering.
Due to the nature of the small closely mounted tiles, mosaic offers good slip resistance with a practical finish ideal for most areas including wet rooms, bathrooms, showers and steam rooms.
Before commencing the installation of mosaic it is important to read the following instructions carefully. The surfaces to be tiled should be smooth, flat, solid, dry and perfectly clean. It is advised to grind down any irregularities wherever possible as these will affect the smoothness of the finished mosaic.
When marking out the surface to be tiled the sheets should be fixed in a staggered brick pattern, allowing for a grout joint between each sheet. This will enable fixing to be as accurate as possible using the joint widths on the sheets as a guide.
Fixing Paper Faced Mosaic:
Install the mosaic with the paper sheet facing towards you. Using a 3mm trowel spread the adhesive over one square metre with the toothed edge of the trowel, keeping the comb lines parallel. Press the mosaic sheets into the adhesive, ensuring that any images or words printed on the paper are facing the same direction. Use the gaps between the tiles to regulate the sheet spacing and tap the sheets flat using a rubber float to ensure proper adhesion. Do not use a metal float. After laying another square metre, go back to the previous fixed square metre and wet the sheets. Care should be taken not to wet the paper too much as the adhesive will not have cured. Give the moisture time to penetrate the paper and dissolve the glue, usually 5 – 10 minutes. Starting from one corner, carefully pull the paper off the mosaic diagonally keeping close to the surface. This must be done carefully so not to dislodge any of the tiles. If this is difficult, stop, wet the paper again and leave for a further 5 minutes. Once the paper is free from the mosaic, correct any alignment faults using a small spatula, remove any excess adhesive from the grout joints and allow to dry for the prescribed time before grouting.
Where the sheets are faced with a plastic sheet, soaking will not be necessary. Any alignment adjustments can be made by cutting the plastic with a sharp blade to free the individual tiles. The adhesive must be fully set before attempting to remove the plastic sheet. The sheet should be removed in the same manner as paper, starting in one corner and working diagonally keeping close to the surface.
The above method is generally the most popular, however the British Standard method requires that the paper faced mosaic sheets are grouted before being applied to the adhesive.
Fixing Mesh Mounted Mosaic:
Install the mosaic sheets with the mesh backing being pressed into the adhesive, using a rubber float to ensure proper adhesion. It is important that the grout joints between the sheets are the same as the joints between each tile. Wipe any excess adhesive out of the grout joints and allow to dry for the prescribed time before grouting.
Individual tiles can be cut with a pair of mosaic nippers. The nippers should be applied so that the edge of the tile is in the middle of the jaws. The tile should be arranged so that the jaws are parallel with the direction of the desired cut before pressure is applied.
A whole sheet can be cut by scoring with a tile cutter and breaking the individual pieces to separate the required shape.
In most cases a fine texture grout will be suitable. Where the mosaic has been installed in a wet area or on a floor, a flexible admixture should be added to the mix or a ready flexible grout should be used. In swimming pools or heated spas an epoxy grout should be used. Epoxy offers a higher resistance to the chemicals necessary for water maintenance in these areas.
The area to be grouted should be clean and dry. It is recommended that the grout should be applied over the whole area, taking off any large excess with the edge of the grout float. Remove any excess grout with a damp sponge, rinsing it out frequently with clean water. Once the grout is dry, remove any residue with a solution of Powerclean.
Epoxy grout should be applied in a similar manner, removing any large excess with the edge of the rubber float. Remove excess epoxy grout immediately. Clean with a thoroughly soaked scotchbrite pad ensuring that any residue has been emulsified and suspended within the cleaning water. Care should be taken not to remove the grout from the joints. Wipe the cleaning water away with a sponge, rinsing it out frequently with clean water. Inspect the area closely to ensure no residue has been missed. No residue should be left on the mosaic as the epoxy grout will be extremely hard to remove once dry.