The Big Reveal

Welcome to "Tile Talk"! In this episode, we dive deep into the world of large format tiles (LFTs), typically defined as anything over 15 inches on one side. While they create stunning spaces, LFTs present unique challenges, often requiring more work and special care than smaller tiles. Learn how to avoid common pitfalls like lippage (uneven tile edges) and ensure a flawless, long-lasting installation.


Key Takeaways:


Substrate Preparation is Paramount:


Your floor must be incredibly flat, with no more than 1/8 inch variation within 10 feet and no more than 1/16 inch out of plane in 24 inches.


Self-leveling underlayment is highly recommended to achieve this crucial flatness, saving time and preventing guesswork with mortar thickness.


Mortar Matters: The Right Adhesive and Technique:


Always use a medium bed mortar specifically rated for Large and Heavy Tile (LHT or LFT), as it provides the necessary thickness, full coverage, and strong bond for oversized tiles.


"Key in" or "burn in" the mortar to the substrate using the flat side of your trowel to ensure mechanical lock and optimal bonding.


Back-buttering the tile is essential; apply a thin, even layer of mortar to the back of the tile itself. This helps account for natural tile warpage and ensures maximum coverage.


Use a large-notch trowel (e.g., half-inch by half-inch) for proper adhesion and coverage. Aim for at least 80% mortar coverage (95% in wet areas).


Managing Imperfections and Ensuring a Smooth Surface:


Large format tiles can naturally warp or dome in the middle; this is normal and not a defect.


Leveling clip systems are almost a necessity to pull tiles together and achieve consistent, lippage-free joints.


Consider wider grout joints. Industry standards recommend at least three times the facial dimension variance of the tile to manage natural size variations and reduce lippage. Limit tile offsets to 33% to minimize lippage.


Cutting and Handling Large Format Tiles:


When cutting, support the entire tile to prevent sprawling or breaking; heavy pieces hanging unsupported can crack. Place tiles on rigid insulation or foam board to reduce vibration.


Score the tile first and cut slowly using a back-and-forth motion with multiple passes to reduce tension and prevent cracks.


These tiles are heavy, so use a dolly or other moving tools to transport them, and don't hesitate to work in teams or "call a friend" to prevent fatigue and injury.