b'ASK THE EXPERTSAsk the Experts Q&As are culled from member inquiries to NTCAs Technical Support staff. To become a member and make use of personal, targeted answers from Technical Support staff to your installation ques-tions, contact Jim Olson at jim@tile-assn.com.QUESTION bedding coat only (no fi nish coats). WehaveaprojectwithwallNail heads one coat only.tilesthatare4x40,8hexTomyunderstandingprimeris and large 24 x 47-1/8. The gen- notneeded.Wedorecommend eral contractor has drywall fi guredslightlydampeningthesurfaceof andstatesthatjointsorcornersthedrywalltohelpensurethe shouldnt have to be mudded/doneboard does not prematurely draw by the drywall installer nor primed!themoistureoutofthethin-set Our tile installer said that he wantsbond coat.thejointsandcornerscompleted Robb Roderick, andeverythingprimedbeforeheNTCA Technical Trainerwill install. These areas are not in a wet area. However, the large tile is(continued)at a fi replace wall. Q: Would you say primer is the What is correct? responsibility of the tile installer or drywall installer?ANSWERThere are two recognized meth- A: If we are going to put tile onto ods for installation of tile over gyp- the drywall surface and the primer sum board found in the Tile Councilis necessary to prepare the drywall ofNorthAmericaHandbook.forasuccessfultileinstallation, TheyaremethodsW243(thin- this would be the responsibility of set) and W242 (organic adhesive).the tile contractor and not the dry-Both have a section of the meth- wall contractor.odthataretitled Preparationby OtherTrades.In that section it states gypsumboard shallbeinstalled per GA 216 treat-edwithtapeand jointcompound,TCNA Handbook Methods (l.) W242 and (r.) W243.26 TileLetter | November 2019'