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 124ASK THE EXPERTS QUESTION I have a bathroom that was just retiled floor tub and shower walls using ceramic tile and a polymer- modified cement-based sanded grout with a stain-resistant additive. There are a few areas where the grout has set up like powder and can be rubbed out. Im looking for some reasons that could cause the grout to set up like powder and fall out. ANSWER Selection mixing installation curing cleaning and environmen- tal conditions at the time of grout- ing all play a critical role in the success of the installation. There are many potential reasons for this to have occurred. Most are related to improper preparation mixing proportioning of powder and liquid slaking re- tempering or curing of the grout. Environmental conditions at the time of grouting and curing such as exposure to hot air flow direct sunlight a very dry atmosphere or freezing could also cause this con- dition to occur. Over-washing of the grout imme- diately after packing the joints or cleaning cured grout with acidic cleaners may contribute to this problem. In some instances a very highly- absorptive tile or foreign material in the joints may cause rapid dehy- dration of the grout that may lead to this happening. Without knowing the particulars at the time of your grout installa- tion it is not possible to narrow it down further to a specific cause or group of causes. Mark Heinlein NTCA Technical Trainer FURTHER COMMENT That is very helpful. What would the needed fix be regarding the powdery grout Does it have to be removed and re-grouted RESPONSE It may be possible to slowly Sponsored by 20 TileLetter June 2016