For the pool owner who is getting a new pool or having their pool re-finished, adding Ceramic Mosaic Art to their project can be a fun and rewarding activity, not to mention saving a few dollars by installing them yourself. Installing Swimming Pool Mosaics is not too dissimilar to tiling an interior floor or wall, in fact, in some ways, much simpler. The time to install your mosaics is just before, a day or two, the finish plaster is applied. In this article I will explain what equipment and materials are required, surface preparation and a step by step installation procedure.
Needed Equipment and Materials
There is nothing special about the equipment and material that you will need. They can be found at most hardware store. The required tools are:
- Trowel with a 3/8” serrated edge
- Two buckets, one for mixing and one for fresh water
- Stirring paddle that fits on a hand drill
- Rubber gloves
- Utility knife
- Scrub brush
- Large Sponge
The only material, other that the mosaics, are a bag of white, sanded thin set, a bottle of muriatic acid and grout.
Swimming Pool Mosaics come completely assembled. In the case of larger Swimming Pool Mosaics they may come in two or more sections. The mosaic is designed so that the finish coat fills in the space between the individual ceramic pieces. On a horizontal or vertical surface, the finish coat will go in-between the pieces and seep down under the mosaic thereby making a solid bond between the surface and the mosaic. The only exception is if the finish coat has pebbles in it. The pebbles are too large to fit in-between the ceramic pieces. In this case the mosaic will need to be grouted after it is installed.
Note: DO NOT let the mosaic get WET. The individual pieces are held onto the screen backing with white glue and will fall off if they get wet!!!
Begin by removing the mosaic from its cardboard backing. Cut as close to the ceramic perimeter as possible. Place the mosaic where you want it and draw an outline with the chalk. The purpose of the outline is to act as a guide when you apply the thin set. For items installed on a vertical surface, make sure the top of the mosaic is at least 18” below the surface of the water. The surface of the water, the water line, when the pool is full, is about 3” below the top of the water line tile.
Next, put on the rubber gloves; dilute the acid 50/50 with water. Remember, the acid is poured into the water! Apply with a scrub brush. No need to scrub very much. Let the acid do the work. Rinse. The outline may have to be re-drawn. If so, go ahead and draw the outline now before the area dries. You may need to hold the mosaic on the cleaned area to get the outline re-drawn. Let the area dry. The acid kills bacteria that may be growing in the gunite.
While the area is drying, mix the thin set. Mix the water and thin set to a consistency of pizza dough. Do not make it runny. The thin set needs to hole the mosaic on the vertical surface even when it is wet. Also, if the thin set is too runny, it will seep into the grout lines preventing the finish coat from getting into the grout lines. Use the outline as a guide when applying the thin set mixture. Spread the thin set with the trowel out past the outline a little. Make the area about 3/8" thick. Use the 3/8” serrated edge of the trowel as a way to insure the proper thickness. Now apply the Swimming Pool Mosaic. Push it into the thin set a little. Use a damp sponge (make sure you ring the water out of the sponge) to level the mosaic. Use the straight edge of the trowel to remove excess thin set from around the edge of the mosaic. I will often use the sponge to get as much thin set away from the edge of the mosaic as possible. You want as much finish coat to touch the edge of the mosaic as possible. Don’t worry about a white film left on the mosaic. The film will get cleaned off by the finishers. If you are getting a finish coat that includes pebbles, now is the time to put grout into the grout lines of your mosaic. Just mix the grout per the instructions on the bag. Fill the grout line to be flush with the top surface of the mosaic. Again use your sponge to clean off excess grout material. Voile`, you’re done. Step back and admire your work!
Speaking of the finishers, most finishing companies use a machine to blow the plaster coat onto the gunite surface. During this process your mosaics will get covered up. That is an important step because the finish coat needs to seep into the space, grout lines, between each piece that makes up the mosaic. The finishers will sponge off the excess plaster to the best of their ability. However, I strongly recommend that you supervise this step because they may not see all of the mosaics you have installed or they may not uncover all the little pieces, such as one of the flippers on a turtle. In the 20 years that I have been involved with Swimming Pool Mosaics, I have had only two cases where customers called to tell that the finishers had not completely uncovered all the little pieces. The unfortunate thing is that once the finish coat is dried, any attempt to scrape the material off the mosaic can damage the integrity of the finish coat and may void your warranty. So watching the finishers is a good way to prevent this from happening.