b'ASK THE EXPERTSand what is the allowable varianceexplain how installations that meet intheactualtile-to-tileinstalla- industry standards for lippage can tion, and also information how tolookpoorlyundertheselighting resolve this besides tearing out theconditions.Someinstallersinthe walls? Thank you!samesituationwillturnoffthe lightsandputadifferentlight ANSWER sourceonatadifferentangleon InChapter6oftheNTCAthesamewall.Theythendocu-ReferenceManualthereisasec- ment both lighting situations with tion called Critical Lighting, as wellphotos, showing this to their cus-as a Lighting and Tile Installationstomerstoexplaintheeffectlight sectionintheTCNAHandbookcan have on the appearance of the for Ceramic, Glass and Stone Tileinstallation. I would check to make Installation. They both address thissure the installation is in tolerance problem. There are also standardsforlippage.Then,Iwouldtake inbothTCNAandANSIabouttheNTCAReferenceManualand allowable lippage. For the tile andTCNA Handbook to your customer groutjointsizeyouareusinginshowingthemwhatourindustry this installation, the allowable lip- saysaboutthistypeoflighting.I page is 1/32, which is about thehope this helps. thickness of a credit card.Robb Roderick, ThesectionsaboutlightingNTCA Technical Trainer26 TileLetter | May 2020'