P
Perry
yes used to see this a lot about twenty five years ago around windows anywhere where the adhesive was packed out or more than 6mm, the substrate was non porous
ask the customer what they have used to clean the tiles ( if they have ),cant see it being anything to do with the adhesive if you have used bucket adhesive a lot on here dont use it but i use it most of the time without any problems at,, all get in touch with bal technical and they should do a test on the adhesive for you
haven't seen anyone using tubbed adhesive for 25 years lolGrouting before the tubbed adhesive has set can result in the moisture trying to still escape through a now grouted joint and will stain grout.
As Pete said , due to using tubbed adhesive too thick. I have seen it a few times.
If it was the customer cleaning with bleach , then it would be uniform grout discolouration.
Dave i come on here to try and help people,most of my posts get a stupid comment from you ,like you think i dont know what i am talking about ,i will tell you once more ,i have been doing this job for well over forty years ,i have fixed tiles with sand and cement before adhesive arrived i remember bal tad comming onto the market when i was a apprentice and bal is now one of the biggest adhesive companies if you dont use bucket adhesive that is fine but dont make out that it cant be used i have fixed many many mtrs of tiles using tubbed adhesive most days without problems,pjc have you not worked for twenty five years lol or not seen any other tilers in anywhere you use buying it? not everybody uses powder,back to the problem like i said Bal have a good tecnical dept
sorry Brian i am not having a go at anyone but i have mainly been tiling floors over the last 20 years but i used to get asked by several companies to have a look at their tiling problems with bal grout the most common problem was moisture coming out of the grout from behind due to thick adhesive or on top of glazed tiles so not drying before it was grouted Pete