The TCNA Handbook for Ceramic Tile Installation (Tile Council of North America) is the authoritative reference for residential tile installation. Key requirements: floor substrate deflection maximum L/360 (may require additional subfloor blocking or stiffening); wet area waterproofing in shower floors and walls — Schluter Kerdi, Wedi, or Redgard are common systems; large format tile (15+ inch side) requires flatness of 1/8 inch in 10 feet — tighter than standard subfloor tolerance — and medium-bed mortar; grout joint minimum width set by tile manufacturer (typically 1/16–3/16 inch for rectified; 3/16 inch for non-rectified); and movement joints at all changes of plane, changes in substrate, and at maximum 20-foot intervals in field — filled with compressible caulk, not grout. These are not optional recommendations; they are the standards that govern successful tile installation and warranty compliance.