b'ASK THE EXPERTSthat meets the ANSI A108 require- Many tile factories are excellent at ments for fl atness controllingwarpage,butitcannotFollowingtheANSIA108.02be completely removed. That is why 4.3.8.2and/orthetilemanufac- there are limits for how much warp-turers requirements for maximumage a tile can have detailed in ANSI offset A137.1fortilesthataremanufac- Following the details of the appro- tured to meet that standard. Whether priatemethodselectedfromtheor not a given tile meets the warpage TCNAHandbookforCeramic,limit of ANSI 137.1 can be found in Glass, and Stone Tile Installation the information printed on the car- Selectingthecorrectmortarorton or on the manufacturers techni-adhesive for the type of tile beingcal data sheet, or by contacting the installed and application it is to bemanufacturer.installed in You are absolutely correct in not- Mixing the mortar or adhesive peringthatlippageresultingfroma its manufacturers instructions layout or offset pattern or other fac- Selectingthecorrecttrowelandtorscanbecomearealproblem usingitcorrectlytoachievethewhen the lights are turned on. This bond coat coverage rates requiredis especially true for walls when the for the system equals a successful,lighting grazes the face of the wall long-lastinginstallationthatwillorwhenthereisasharpangleof please the owner and end user.Notethat ANSI A108.024.3.8.2 states .specifi er and owner must approve the mockup and lippage. In my opinion, the expense of pur-chasing an adequate percentage of tiletoinstalltherequiredoffsets can be very minimal when weighed againstthepotentialforlippage and lighting-related failures that can occurwhenmanufacturerinstruc-tions and tile industry standards are not followed.Industrystandardsandmanufac-turerrecommendationsof33%or less offset for tiles with one or more sides15orgreaterarerequired becauseofthemanufacturingpro-cessfortile.Whenceramictileis heated and cooled in the kiln, warp-agecanoccur.ThisisanormalLippage can become a real problem when result of the manufacturing process.the lights are turned on.30 TileLetter | May 2019'