Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Page 21 Page 22 Page 23 Page 24 Page 25 Page 26 Page 27 Page 28 Page 29 Page 30 Page 31 Page 32 Page 33 Page 34 Page 35 Page 36 Page 37 Page 38 Page 39 Page 40 Page 41 Page 42 Page 43 Page 44 Page 45 Page 46 Page 47 Page 48 Page 49 Page 50 Page 51 Page 52 Page 53 Page 54 Page 55 Page 56 Page 57 Page 58 Page 59 Page 60 Page 61 Page 62 Page 63 Page 64 Page 65 Page 66 Page 67 Page 68 Page 69 Page 70 Page 71 Page 72 Page 73 Page 74 Page 75 Page 76 Page 77 Page 78 Page 79 Page 80 Page 81 Page 82 Page 83 Page 84 Page 85 Page 86 Page 87 Page 88 Page 89 Page 90 Page 91 Page 92 Page 93 Page 94 Page 95 Page 96 Page 97 Page 98 Page 99 Page 100 Page 101 Page 102 Page 103 Page 104 Page 105 Page 106 Page 107 Page 108 Page 109 Page 110 Page 111 Page 112 Page 113 Page 114 Page 115 Page 116 Page 117 Page 118 Page 119 Page 120 Page 121 Page 122 Page 123 Page 124 Page 125 Page 126 Page 127 Page 128Failure to use an approved weep protector with this cited method can contribute to the problem. “Checking the weeps prior to instal- lation plays an important role in the installation process,” Brookes said. “I have witnessed casting burrs on the cast iron flanges from manufac- turing that could cause problems with inadequate drainage. They must be checked and if necessary, drilled out so that they can function properly.” A curious characteristic of stone/tile staining is that dark discoloration does not always migrate or cross from one tile to the next, Brookes added. “It’s almost like you can see the square sheets of tile,” he said. “It may be that the grout causes a capillary break between each stone, especially if a dense, single-component or epoxy grout is used.” This is not a problem limited to inex- perienced installers. “We have seen installs by competent installers who have claimed to do everything by the book,” Brookes said, and it still occurs, typically with lighter-colored stones. “We don’t know if this is because it’s more obvious with these stones and it actually is occurring with others but isn’t noticeable,” he said. To investigate and help solve this phenomenon, Brookes and Young recommend that installers check the back side of mosaics before instal- lation, looking for mineral content – namely iron oxide. Brookes said that mineral compounds, “ if exposed to prolonged levels of moisture, would manifest into a orange/ brown stain- ing.” Installers are also asked to exam- ine types of backing and check if they are water-soluble or resin-based. If so, it’s recommended to request of manufacturers – before installation – an installation guideline or assurance that this type of material can be used in a continuous wet area or exposed to prolonged periods of moisture. Brookes said that the investigation is ongoing. “Steve Young created a checklist for installers to fill out pre- installation, during, and post-installa- tion with full documentation of decon- struction if there in a problem,” he said. “We ask that all installers do this if possible, logging all types of materi- als, methods, temperature and when put into service, so if the install devel- ––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––– STONE TileLetter | February 2017 65