Swimming Pool Blog
by Rob Cox, May 29
How to Repair Swimming Pool Tile in 5 Easy Steps
Sooner or later, the tile in your in-ground gunite pool will begin to loosen and fall off one by one. Every 25 years or so, a complete re-tile of the pool may be necessary. In between, you can do simple, quick repairs to re-attach pool tiles that have fallen off.
With the use of some simple tools, and a simple cement product, small tile repair jobs can be done in a short amount of time. Larger runs of several feet, or entire sides of the pool, can also be done by the pool owner. However, more time and materials will be needed.
Step 1: Remove loose tile with a small flathead screwdriver or chisel. Remove the grout stuck onto the sides of the pieces with small pliers. Using a small, sharp screwdriver, remove any old grout that remains stuck to the pool wall, or on adjacent pool tile still attached.
Step 2: Prepare the bed (the wall behind the tile) by removing any loose or flaking material. The video below describes how to build up the bed, if needed, to have a smooth vertical surface that's even with the other tile. It is important to preserve the ledge, or lip underneath the bottom tile, to help hold the vertical tiles. You can create a nice 1/8 in. deep lip or ledge with a 4 in. Grinder with a masonry or diamond blade, before removing the tile, if you want to replace the entire height of tile.
CRACKS BEHIND THE TILE?
If there are large cracks in the beam (the area of the pool wall behind the tile), stop! These should be opened up and filled with hydraulic cement, pushing the cement as far as possible into the crack, to reduce the possibility that your tile will fall off too soon. Pay attention to large cracks in the beam, as these are likely the cause of the tile coming off in the first place. Such cracks are often caused by a faulty expansion joint, allowing the pool and pool deck to touch during expansion and contraction. As they both expand, the deck wins, pushing into the pool wall.
In cases of active beam damage, expect a tile repair to only last a year or two unless the larger issues are dealt with. In worst cases, this involves removing the coping stones, and replacing the top portion of the wall, and restoring the expansion joint between the pool wall and pool deck. And that is a subject for another blog post, on pool beam repair.
CHUNKS MISSING BEHIND THE TILE?
If the facing foundation for your tile job is uneven, with missing chunks of material, these should also be filled in with a pool plaster mix or hydraulic cement (without aggregate), so that we have a smooth base to set the tile against. It is important to not build up this area too much. Otherwise, your new tile will be uneven with the tile on either side.
As mentioned above it is also important to preserve the lip of plaster at the bottom of the tile to support the tile while the mortar dries. If there is no bottom lip, the tile may slip. In such cases you can use strips of duct tape, above or below, to help support the tile until the setting mortar dries (a few hours).
Step 3: Mix up a small batch of Thin Set Mortar. I use EZ Patch #3, Thin Set for Pool Tile Repair. WET THE AREA thoroughly, before applying the Thin Set, so the dry wall won't pull moisture out of your Thin Set. Add water to the thin set powder and mix to a spreadable consistency, something like creamy Peanut Butter (not runny). Use a notched trowel to spread the mix in an even, thin coating of 1/8-3/8 inch thickness. If placing individual pieces of tile, it may be easier to 'back butter' each piece as you go, rather than spreading the Thin Set on the wall. If some of the mixture drops in the pool, no worries it will dissolve. When finished, use the pool brush to clean off any clumps on the pool floor.
Spread enough mixture only on the areas that you can reasonably affix tile to within five minutes. A professional may lay down strips of 3-5 ft. at a time, but for novices, keep it under 12 inches. 6x6 tiles are fastest and easiest to set, but small mosaic tile, especially if you are placing individual pieces, will take more time. Press the pool tile firmly into the thinset mortar bed, until it squeezes out from behind and in between. Work fast, before the mortar begins to dry. Do this during a cooler part of the day, or fashion some shade if necessary.
After setting the tile pieces, back up to check your previous work, every few minutes. Tile pieces may begin to slump, or slide down the wall. Without much motion, very slowly push and maneuver the tile back into position. For larger tiles that want to fall off, long, vertical pieces of duct tape can be used to help tape the tile in place temporarily.
Step 4: Grout the tile. After the tile has been set in place for 24 hours, you can use a waterproof tile grout to seal all the spaces in between the tile. Thin Set does not work well as grout for this step. I like to use EZ Patch #4, Pool Tile Grout. However, you can use a pool plaster mix as well, like EZ Patch #1. In fact, you can use the plaster mix as setting mud and grout, all-in-one.
Use a flexible spreader to push the grout in between the tiles. You can buy small grout floats or spreaders, or for very small jobs, a stiff piece of cardboard works fairly well. After it has set up for 10-15 minutes, use some water and gentle rubbing to clean up the extra grout that smeared onto the tiles. After 24 hours, you can use a stiff brush or scrubber to remove the haze and polish the tiles.
Step 5: You can fill the pool back up immediately!
See our Pool Info page on Tile for more information about pool tile repair.
If you need to buy replacement tile, visit NPT, or National Pool Tile, one the largest dealers in pool tile. Finding your exact replacement tile can sometimes be difficult, however, for older styles. If you just need a few pieces, you can take them from the skimmer throat, replacing those tiles with a similar color tile. If you need more than a few pieces, you may have to re-do the entire tile band, or settle for a tile that looks similar.