Save time and frustration by carefully following these instructions for installing mosaic tiles.

  • General conditions

    With any tile installation, begin by evaluating the site conditions: temperature and humidity, substrate, waterproofing. For exterior installations you will evaluate the options of either partial or total covering. The substrate must by correctly aged; normal site practice suggested by adhesive manufacturers is to wait 28 days for the underlay and cement based plasters or 90 days for concrete. With anhydrite-based substrates, allow a maximum of 0.5% residual humidity.

    It is also very important to take into account the possible effects of temperature on adhesives and materials. At temperatures below 10° C, proper drying of the adhesive would be considerably slowed down and could create problems for bonding in the long term; at temperatures over 35° C it is advisable to carry out the installation at a time day with less sun, generally in the morning or late afternoon. Shield the site from excessive sunlight during the hottest parts of the day to prevent possible dehydration of the adhesive.

    It is equally important to consider the dehydrating effect of the wind, especially during the installation of exterior facades or on boats. In the case of swimming pools it may be necessary to test the bonding to evaluate the behavior of the structure adequately. Shower floors and Jacuzzi tubs must be waterproofed with special products. Before smoothing and laying, all traces of dirt, oil, etc. must be carefully removed; in addition all loose parts must be eliminated and the surface powder removed. 

  • Technical instruments for laying mosaics

    Before beginning, check that all the instruments are clean and without rust.

    · Angle grinder with crown diamond–continuous cutting disc.
    · “Special” diamond disc for cutting mosaics, diam. 110 mm.
    · Measuring set: tape measure and pencil.
    · String for marking the main reference grid.
    · Mosaic pliers and cutter.
    · Set of various-sized trowels - Floats.
    · Toothed spreader (Choose the one suitable for the material to be laid and the
       type of support to be used).
    · Rubber float for grouting and felt-backed float.
    · Basin with roller and sponge for cleaning. 
    · Low speed mixing drill with spiral mixer, necessary to ensure than the
       properties of the adhesives remain consistent.
    · Trend mosaic adhesive.

  • Substrate preparation

    The substrate must be compact and free of cracks. If there is a tendency to flake or if it is warped from shrinking, it will not provide adequate support for the installation;  correct rendering must be carried out first. Rendering is also necessary in all cases where the base is not perfectly flat. With Trend adhesive, it is possible to produce rendering up to 5 mm to correct small defects of the substrate; this operation must be carried out at least 24 hours before laying tile begins. For rendering operations more than 5 mm thick, the use of specific white-color rendering products is advised. 

    Unless otherwise specified by the customer, the mosaic is usually laid on white adhesive to avoid altering its color. If the substrate is grey (especially dark grey), it is advisable to render it with white adhesive to make the color of the substrate uniform before beginning to lay the tiles.

  • Laying mosaic

    Every installation begins with the unpacking of the mosaics. It is advisable to verify the condition of each sheet of mosaic contained in the boxes before beginning to lay, and it is good practice to keep the material to be laid at the same temperature as the surroundings in which the work is being carried out. The starting point is then identified and marked on the wall where the mosaic sheets are to be laid. Mark the guidelines at right angles to each other corresponding to the multiples of the sheets of mosaics previously measured. It is customary to mark squares for 3 x 3 sheets. Of course, in the case of installing tile on a wall, the guidelines must be both horizontal and vertical.

    Once the reference grid has been marked, the adhesive is spread over the base. First use the smooth edge of the notched spreader to ensure that the whole surface is covered. Excess adhesive is then removed using the notched edge of the spreader (3 mm square teeth), being careful to keep a steady inclination of the spreader and exerting sufficient pressure so that no more adhesive than necessary remains on the base.

  • Laying mosaic on film

    Once the reference grid has been marked and the adhesive spread over the base, the actual installation begins by applying the mosaic sheet with the plastic film facing towards the operator (not towards the surface) and without exerting too much pressure.

    Tap the mosaic with the rubber float to ensure perfect adhesion to the surface. During this operation it is possible to correct any minor errors that might have been made in the alignment by lightly tapping sideways on the sheets.

    The adhesive must not run over the joints. If this should happen, it means (1) that the notches on the spreader are too large; (2) that the base for laying is not perfectly flat and in some points there is excessive adhesive; or (3) that the notched spreader is not being used correctly. 

    During the installation some manual manipulation on the sheets of mosaics may be necessary.  When this is required, the installer simply removes a single tile and substitutes it with another, being careful to ensure that the adhesive is still workable.

    The plastic film is removed from the mosaic only when the adhesive is sufficiently hardened; the suggested time is approximately three hours. The motion should be carried out diagonally, keeping the film parallel to the tiles themselves. If during the removal of the film the mosaic should move, it is necessary to wait longer.

  • Laying paper face mounted mosaic

    If the mosaic as been assembled using paper on its face, the paper should be facing the installer during the various phases of the installation.

    It will facilitate the installation if you will examine the paper and notice the small stripes running through the paper. These stripes should be positioned vertically on the surface.

    Pay special attention at the distance/joint between the pieces of mosaic on the sheet. The same distance should be maintained between the sheets as they are installed. Once the sheets are installed, use the rubber float to tap the mosaic into the adhesive and use the proper trowel to flatten the sheet. 

    The removal of the paper is performed using warm water and a sponge. Repeat the gentle sponging operation in the area you are working until you can remove the paper easily. You can also use a steamer to facilitate this process. Work carefully, because at this stage the adhesive may still be relatively fresh.

    When removing the paper, pull diagonally from one top corner to the opposite bottom corner of the sheet. With the adhesive still somewhat fresh you can adjust the grout lines and improve the visual impact of the finished project.

  • Grouting and final cleaning

    Do not compromise on the minimum times for allowing the adhesive to set before filling the joints: 24 hours for vertical walls and 48 hours for floors to allow them to be walked on.

    Using the rubber float, spread the grouting cement with vertical and horizontal strokes exerting a slight pressure to make sure the joints are well-filled. Pass diagonally to remove most of the excess filling.

    The cleaning of the surface can begin once the grouting cement starts setting. This time will vary according to the temperature of the surroundings, but will be between 30 and 60 minutes. Remove the excess grouting material using the special felt and a slightly dampened sponge; at all times be careful not to remove the filling from the joints.

    It is very important to carry out this operation before the grout has completely hardened. Any eventual residue can be removed with a special acid-based product for the removal of residue cements. Be sure to rinse everything thoroughly after this operation to avoid leaving traces of acid.

    If there are any traces of adhesive on the tiles at the end of the job, after having stuccoed the mosaic, remove the dry excess with steel wool.

  • Technical information catalogue

    CLICK HERE to download "My Tech" the technical information catalogue.

Cleaning mosaic

After a professional installation, your glass mosaic will look absolutely stunning. In its power to generate light and color around your house or your commercial environment, it is unmatched by any other material.

Better yet, Glass Mosaic is basically maintenance-free. Many products are marketed as “professional mosaic cleaners” but our experience is that the use of a generic glass-cleaning product like “ Windex”...


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