🧱 Tiling

What you’ll learn

1. Tile Never Fails. The Thing Under It Does.Establish the course's central claim: tile is a rigid, brittle skin over a substrate that moves, so every failure is a movement problem or a bond problem.Porcelain is enormously strong in compression and nearly incapable of bending. Set it over something that flexes, or bond it incompletely, and it cracks — not because the tile was weak, but because it was asked to do something no ceramic can do. Every failure in this course traces back to one of those two causes.
2. The Substrate DecidesUnderstand deflection limits (L/360 and L/720), what flatness means, and what backer board and uncoupling membranes actually do.Industry standards require a substrate no more flexible than L/360 for ceramic and porcelain, and L/720 for natural stone over wood. Backer board provides a bondable, water-tolerant surface but adds almost no stiffness — a distinction that causes real failures. Flatness is not levelness, and large tile punishes both.
3. Thinset Isn't GlueUnderstand thinset as a hydrating cement mortar, and why open time and mortar coverage determine whether tile stays attached.Thinset cures by a chemical reaction, not by drying, so it cannot be revived and it skins over on a clock you don't control. ANSI A108.5 requires 80% average mortar contact on interior dry floors and 95% in wet and exterior areas, with no void larger than two square inches — and the technique that achieves it is directional troweling plus the habit of pulling a tile to check.
4. Layout: The Decisions You Make Before Any MortarPlan a tile layout from reference lines rather than walls, control where cuts land, and understand grout joints and offset limits.No room is square, so starting against a wall inherits and accumulates its error. Professionals lay out from snapped reference lines squared with a 3-4-5 triangle, place cuts where the eye doesn't go, and keep no cut smaller than about half a tile. Grout joints exist to absorb real dimensional variation, and ANSI limits offset to 33% on tiles over 15 inches.
5. Cutting Tile Without Breathing ItUnderstand how each tile-cutting method works and why silica dust control is part of the cutting technique itself.A snap cutter propagates a controlled fracture; a diamond blade grinds rather than cuts. Both produce a hazard: tile, porcelain, and stone contain crystalline silica, and dry cutting generates respirable dust well above OSHA's 50 µg/m³ limit. Water on the blade is not a nicety — it is the dust control, and it is the reason wet cutting is standard practice.
6. Grout, and What the Joint Is ForUnderstand what grout does and does not do, choose between grout types, and pack and clean a joint properly.Grout is neither adhesive nor waterproofing. It fills the joint, keeps debris out, and transfers a little load between tiles. Sanded and unsanded are about shrinkage, not scratching; epoxy trades forgiveness for performance. Most grout failures are packing failures or a too-wet sponge.
7. Movement Has to Go Somewhere. So Does Water.Understand movement joints, why grout in a corner always cracks, and why a tiled shower is water-managed rather than waterproof.Rigid materials bonded together with different movement rates build stress until something fails. Movement joints — flexible sealant at the perimeter and at every change of plane — are where that stress is released. Water, meanwhile, always gets past tile and grout; a shower works because a continuous membrane behind the tile drains it back out.
8. How to Read a FailureDiagnose real tile failures by sorting symptoms into movement and bond causes, and choose an appropriate first project.Every failure in this course sorts into two buckets. Hollow tiles and clean-backed tiles are bond failures; straight cracks, corner cracks, and tenting are movement failures. The right first project is a dry, flat, low-consequence backsplash — and the professional advantage is decision-making, not hand speed.

Questions this course answers

Grounded in trusted sources

• ANSI A108 / A118 / A137.1 — American National Standards for the installation of ceramic tile
• Tile Council of North America (TCNA) — Handbook for Ceramic, Glass, and Stone Tile Installation
• TCNA — Rectangular Tiles: How to "Offset" Certain Installation Challenges (https://tcnatile.com/wp-content/uploads/2022/08/Rectangular-Tiles-How-to-Offset-Certain-Installation-Challenges.pdf)
• Ceramic Tile and Stone Consultants (CTaSC) — thin-set coverage standards (https://ctasc.com/expert-answers/what-are-the-standards-for-thin-set-adhesive-coverage-contact-for-ceramic-tile/)
• Ceramic Tile and Stone Consultants (CTaSC) — allowable substrate deflection (https://ctasc.com/expert-answers/what-is-the-allowable-deflection-of-a-substrate-suitable-for-a-porcelain-tile/)
• OSHA 29 CFR 1926.1153 — Respirable Crystalline Silica in construction, incl. Table 1 (https://www.osha.gov/laws-regs/regulations/standardnumber/1926/1926.1153)
• OSHA Fact Sheet 3681 — Crystalline Silica Rule: Construction (https://www.osha.gov/sites/default/files/publications/OSHA3681.pdf)
• Ceramic Tile Education Foundation (CTEF) — trowel selection, mortar coverage, and installation standards

Every Wunder lesson is built from real, reputable sources — never invented.

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