Re: No-caulk shower?
dgbldr,
Am I missing something here? Some stone tiles are so porous that they are unsuitable for anything except decorative (only) installations. I have consulted on many stone installations where the tiles cracked, spalled, conducted water, etc. Personally, if I know - after simple testing - that a particular stone allows the transmission of water, I will not use it in a wet-area application. That said, if the customer insists on a porous stone and is willing to sign a disclaimer absolving me of ANY problems with the installation or associated parts (enclosures and the like), I will install the stone tiles as selected.
It is neither my intention nor desire to dispute your experience with porous tiles, or your abilitiy as an installer. When I first began installing stone tiles, I got many complaints from customers. That was a time when I was not very scrupulous about adhesive contact, grout density, or sealing. Once I became aware of the role of adhesive and grout, and once I had gained experience with sealers and impregnators, though, the complaints stopped.
My question to you is: how long does it take for water applied to the surface of your marble or granite to soak through to the back? To put this in context, if it takes 24 to 48-hours for the water to soak through, and the shower will only be used for an hour or two each day, and the bathroom is adequately ventilated, I would not expect a problem. However, if the same installation is subject to so much water that it cannot completely dry out between uses, there will be a problem.
Perhaps it is the way I finish porous stone tiles that makes a difference. This is assuming that the grout is very dense, and there are no adhesive voids behind the tiles. I will use my own shower for an example. The tiles used are relatively inexpensive "Indiian" slate. The wooden crate these tiles were shipped in was covered with a green mold - probably because wet (freshly cut) wood was used to construct the crate, or the crate was exposed to water during shipping, or while waiting for customs to clear the shipment, the tiles (and wet crates) were warehoused where there was insufficient ventilation for the water to evaporate. Some of the tiles making contact with the crate also presented some mold. I mention the mold because normally, I would not want to use such a stone. But I loved the look and was willing to take the risk that I could control moisture once the tiles were put into service.
After the tiles were installed, I finished the tiles with a method I have used for over thirty years: After allowing the grout to fully cure and dry, I applied two coats of Watco penetrating oil, with the second coat applied approximately 48-hours after the first. 48-hours after the application of the second coat, I applied Miracle 511 as directed. Miracle is not designed as a waterproofing, but rather as a coating that helps resist staining. Both the Watco and the Miracle are applied to the grout as well as the tiles.
Because the tiles have a rather coarse texture, I scrub the tiles with a stiff brush and some 409 about once every two months to prevent soap residue build-up. During the addition to the installation as mentioned in a previous post, I had the opportunity to examine both the tiles and the setting bed. Here is a tile I would never recommend to a customer, but I saw no evidence that moisture was soaking - or penetrating through - the tiles or the grout. As well, I have never seen a speck of mold growing on either the surface of the grout or the tiles. I did not use bleach or other substance to "sanitize" the original mold, but did use a stiff, dry brush to remove the mold.
I should add to this that I applied a bead of clear silicone to the movement joint areas, and while the silicone was still wet and tacky, I dusted the silicone bead with grout powder (same shade as used to grout the tiles). No evidence of mold at the movement joints.
I would not advise the use of Watco or any other penetrating oil for white marble or any other stone that might show yellowing: the one disadvantage when using such an oil over a translucent tile. But I highly recommend a good sealer for any tile in a wet area
Finally, since this post started off as a discussion of weep holes or weep screeds, in my experience inspecting literally thousands of wet-area tile installations - regardless of the tile used - holes, cracks, grout voids, or any other such opening in the surface of the tiles - mold has been a problem.
dgbldr,
Am I missing something here? Some stone tiles are so porous that they are unsuitable for anything except decorative (only) installations. I have consulted on many stone installations where the tiles cracked, spalled, conducted water, etc. Personally, if I know - after simple testing - that a particular stone allows the transmission of water, I will not use it in a wet-area application. That said, if the customer insists on a porous stone and is willing to sign a disclaimer absolving me of ANY problems with the installation or associated parts (enclosures and the like), I will install the stone tiles as selected.
It is neither my intention nor desire to dispute your experience with porous tiles, or your abilitiy as an installer. When I first began installing stone tiles, I got many complaints from customers. That was a time when I was not very scrupulous about adhesive contact, grout density, or sealing. Once I became aware of the role of adhesive and grout, and once I had gained experience with sealers and impregnators, though, the complaints stopped.
My question to you is: how long does it take for water applied to the surface of your marble or granite to soak through to the back? To put this in context, if it takes 24 to 48-hours for the water to soak through, and the shower will only be used for an hour or two each day, and the bathroom is adequately ventilated, I would not expect a problem. However, if the same installation is subject to so much water that it cannot completely dry out between uses, there will be a problem.
Perhaps it is the way I finish porous stone tiles that makes a difference. This is assuming that the grout is very dense, and there are no adhesive voids behind the tiles. I will use my own shower for an example. The tiles used are relatively inexpensive "Indiian" slate. The wooden crate these tiles were shipped in was covered with a green mold - probably because wet (freshly cut) wood was used to construct the crate, or the crate was exposed to water during shipping, or while waiting for customs to clear the shipment, the tiles (and wet crates) were warehoused where there was insufficient ventilation for the water to evaporate. Some of the tiles making contact with the crate also presented some mold. I mention the mold because normally, I would not want to use such a stone. But I loved the look and was willing to take the risk that I could control moisture once the tiles were put into service.
After the tiles were installed, I finished the tiles with a method I have used for over thirty years: After allowing the grout to fully cure and dry, I applied two coats of Watco penetrating oil, with the second coat applied approximately 48-hours after the first. 48-hours after the application of the second coat, I applied Miracle 511 as directed. Miracle is not designed as a waterproofing, but rather as a coating that helps resist staining. Both the Watco and the Miracle are applied to the grout as well as the tiles.
Because the tiles have a rather coarse texture, I scrub the tiles with a stiff brush and some 409 about once every two months to prevent soap residue build-up. During the addition to the installation as mentioned in a previous post, I had the opportunity to examine both the tiles and the setting bed. Here is a tile I would never recommend to a customer, but I saw no evidence that moisture was soaking - or penetrating through - the tiles or the grout. As well, I have never seen a speck of mold growing on either the surface of the grout or the tiles. I did not use bleach or other substance to "sanitize" the original mold, but did use a stiff, dry brush to remove the mold.
I should add to this that I applied a bead of clear silicone to the movement joint areas, and while the silicone was still wet and tacky, I dusted the silicone bead with grout powder (same shade as used to grout the tiles). No evidence of mold at the movement joints.
I would not advise the use of Watco or any other penetrating oil for white marble or any other stone that might show yellowing: the one disadvantage when using such an oil over a translucent tile. But I highly recommend a good sealer for any tile in a wet area
Finally, since this post started off as a discussion of weep holes or weep screeds, in my experience inspecting literally thousands of wet-area tile installations - regardless of the tile used - holes, cracks, grout voids, or any other such opening in the surface of the tiles - mold has been a problem.
Comment