tiledek waterproof underlayment membrane is the ideal solution for reliable waterproof performance in exterior tile deck or tile roof deck assemblies.
answer answer - if the ceramic tile is already installed there is no way to fully waterproof the floor after the fact, unless you replace the tile and install a legitimate waterproof membrane during the replacement process. some people will try to put a sealer on the grout joints, but that doesn't waterproof it. it doesn't work. it only makes it more water resistant.
tiling over exterior deck or balcony. how do i tile over an exterior deck or balcony? remember that exterior tile systems over inhabited space need a waterproof substrate below the tile. without such, water will be able to penetrate below the tile layer and could cause damage. even when tiling over areas not over inhabited space
wood porch with a tile deck john carroll a schluter-ditra membrane was used to waterproof and prep the floor for tile. before installing it, the author cut and dry-fit all the pieces, marking their position with a pencil before rolling them back up, so he would know where to start and stop the thinset while spreading it over the backerboard
amazon.com: waterproof floor tiles. b2us4630 deck and patio flooring interlocking tiles perforated pack, gray, 30-pack. 4.3 out of 5 stars 139. $74.99 $ 74. 99. free shipping. bare decor ez-floor interlocking flooring tiles in solid teak wood oiled finish set of 10 , long 9 slat.
the decking doesnt leak or squeak, and we havent experienced any color fading problems. i havent mentioned sheet membrane products such as seven trust or waterproof deck-tile installations, because to my mind those waterproofing methods require specialized subs and so fall into a different category.