CHALLENGE
Tile is the finish that shows every mistake made underneath it. A floor out of flat by an eighth of an inch telegraphs through large-format porcelain as lippage on every edge. A shower pan that was never flood-tested fails behind finished tile, where putting it right means demolishing the room. And across more than forty bathrooms the work has to come out the same every time — the same coverage behind the tile, the same joint, the same cure — whether it is a guest bath or a waterfront pool terrace.
SOLUTION
Substrate first. Every surface checked for flatness before a notch was cut, against the ANSI A108.02 tolerance of 1/8 inch in 10 feet that applies to tile with any edge of 15 inches or more, and corrected with a cement-based patch or a self-leveling underlayment rather than buried in mortar. Wet areas built to ANSI A118.10: a bonded, load-bearing waterproof membrane over pan, curb and walls to the required height, corners and drain flange reinforced, and a 24-hour flood test held and recorded before the first tile went down. Cracked or dissimilar substrates got an ANSI A118.12 uncoupling and crack-isolation membrane. Setting materials matched to the tile. Porcelain to ANSI A137.1 with water absorption at or below 0.5 per cent, set in improved modified dry-set mortar to ANSI A118.15 — large-format and heavy tile in the LHT grade that resists sag. Trowel sized to the tile: a 1/4 by 3/8 inch square notch on mosaics and small format, 1/2 by 1/2 inch with back-buttering on large format, mortar combed in one direction and the tile beaten in across it. Coverage verified by pulling tile back out of the wet bed — 95 per cent in showers and on exterior decks, 80 per cent on dry interior floors, which is the TCNA minimum checked rather than assumed. Grout to ANSI A118.7, high-performance cement grout. Joint width is not a matter of taste: it follows the tile manufacturer's recommendation for that specific tile, and never goes narrower than the tile's own edge variation will allow — ANSI A108.02 puts the minimum at three times that variation. Within that, 1/16 inch is the joint clients ask for most, and it is what most of this work was set to. Epoxy grout to ANSI A118.3 where the joint had to stand up to cleaning chemicals. Movement joints at every change of plane, at the perimeters and across the field at the spacing TCNA EJ171 calls for, filled with sealant and never with grout: grout in a movement joint is what cracks a terrace two summers later. Cure times kept, which is the part a schedule always tries to take back. Mortar 24 hours before grouting, longer on a cold or humid day. Grout 72 hours before the shower sees water. Seven days before a penetrating sealer on natural stone and on unglazed mosaics. On the exterior pool terrace the assembly was left to cure fully before anything was moved back onto it.
RESULT
More than forty bathrooms across Central Florida — Orange, Osceola, Seminole, Lake and Polk counties — plus a waterfront pool terrace. Seafoam subway over a herringbone pan, marble-look large format over a hexagon floor, penny round, encaustic-pattern floors, glass mosaic and pebble — all of it set to the same standard, with the flood test and the cure logged before the next trade came in. On the ordinary Central Florida bathroom — a floor of about 40 square feet, plus roughly 60 more on the walls of a shower or tub surround — that is about 100 square feet of tile apiece, and forty of them puts the program on the order of 4,000 square feet installed.
Projects
