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Discuss Wet room slate floor tiles flaking in the The Welcome Forum area at

  1. Dan Haugh

    Dan Haugh New to

    North East
    Good Evening Everyone,

    About 2.5 years ago I had the ensuite turned into a semi wet room i.e. two and a half walls where the shower could potentially wet. There hasn't been any problem with water leaking through anywhere but some of the tiles have started to flake (best word I can think of) and also almost like a soap scum on edge of the tiles.

    I have to say the shower is used at least 4 times a day so it gets fair wear, I think we live in an area with high limescale in the water already, but I do regularly clean and reseal the tiles.... maybe every 6 - 9 months.

    I've looked all over the internet for the best possible solution but cant find anything that makes much sense. I have used wet and dry sand paper on one of the tiles as a trial to see how it looks, basically I now have a tile thats polished around the edges and no longer feels like the others underfoot and also it has quite a different colour where the flaking has occurred, although now smooth it is still quite noticeable as something has changed on the tile.

    I haven't touched the other tiles but was hoping for a few tips if any one could help. You will see in the picture below, the tile to the upper right of the drain has been polished but the colour is now lighter or more grey than the black it is in the centre.

    Also you will notice the other tiles to the left of the picture is how the flaking was before I sanded down, those tiles are still as the picture as I didn't think the first tile worked well. Any tips?

    Second problem I have is the edges of the tiles which look like a build up of dirt. I have cleaned the tiles with Grimex over and over to try and get rid of the whitish marks that are appearing now on the tile edges but it won't budge. Probably best seen in the tile to the left of the drain. Again any help would be greatly appreciated.

    If not possible, then I assume that lifting only the affected tiles and replacing them would be a bad idea? Would the all of the tiles on the shower tray have to come up? If so, when putting new tiles down how do I get the adhesive at the edge of the shower tray to seal against the old adhesive still in place under the connecting tiles (or is that what the grout should do)?

    Thanks for taking the time to have a look, would be a big help to get some professional ideas as I'm so close to just ripping them up.

    Slate tile flaking
  2. jcrtiling

    jcrtiling Trusted Advisor Professional Tiler TTA Member Top Contributor

    What are you sealing the tiles with
  3. Dan Haugh

    Dan Haugh New to

    North East
    The tiles were sealed with LTP colour intensifier and stain block, although I would have thought the amount of Grimex and scrubbing that the tiles probably have little to no sealant left on them.
  4. Lithofin BOB

    Lithofin BOB Test, Test, Test, you know it’s for the best. Company Support

    This could possibly be one of two things,

    Whitening to an over applied Impregnator .
    Or water migrating into the edge / face where the Impregnator or grout has failed, this then can migrate into the tile and form a salt/ whitening. Alkaline products will not remove salt trace or fully remove impregnators.

    I would test a suitable stone specific stripping agent .
    If the whitening removes ,this would be dead seal.

    If it remains, you could then test a specific stone acidic product, that then may remove the salt trace from the face. If this has migrated from the edge or below and is under the seal, this will be difficult ,if not impossible to get rid of.
    With any acidic based product, test on a spare stone if you have one- not all slates are acidic resistant.

    If this removes the contamination,leave the area minimum 5-7 days or until fully released of all moisture and re impregnate
    Ensure you remove all excess. You might look at re grouting as a failure is in several areas and again impregnate once this is fully dry. Leave several days to fully cure.

    Don't sand the tiles!!!!
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  5. Dan Haugh

    Dan Haugh New to

    North East
    Thanks for the information, much appreciated. Would you be able to recommend a stone specific stripper? and also an acidic product? Again so much choice and not a great deal of information from the suppliers pages. I do have a spare tile left over from the installation so would try it on there first.

    I'm starting to think that maybe after trying these products and if the don't work, plus having to re-grout anyway. Maybe it would be just as simple to lift the tiles in question and replace them?

    Is there anything I can do to stop the flaking of the tiles? and to deepen the colour of the tiles where the flaking has occurred?

  6. Lithofin BOB

    Lithofin BOB Test, Test, Test, you know it’s for the best. Company Support

    If you using the LTP range , think there's is the power stripper, we have wax off. I would ring there tech line number on the bottles you have, they could also suggest an acidic product suitable for slate- again test or we have builders clean

    Slate shouldn't be flaking, this is possible water damaged excess Impregnator , but your test will tell us.

    After this you could test a suitable "colour enhancer" an Impregnator.
    Do not use a topical sealer which will leave a shine and increase colour, impregnators only- if you get one test on your spare slate first.
    If the slate is spalling , best way to stop it, ensure that the shower is towelled dry after use, impregnate correctly every 6 months, and use the correct maintenance products that will look after the Impregnator- fix the failed grout.
    • Like Like x 1
  7. Localtiler

    Localtiler Trusted Advisor Professional Tiler JOTM Winner Top Contributor

    I think you have a few issues there, grout falling out..
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