ACT Large Format Tile study guide
ACT Large Format Tile · Work through your exam, one topic at a time.
The ACT Large Format Tile credential is an advanced certification for tile installers who work with large-format tile and want independent verification of their skill. It is aimed at experienced setters, crew leads, and installers moving into higher-end residential and commercial work where big panels demand better substrate prep, mortar selection, and lippage control than small tile does. The ACT Large Format Tile study guide has 9 sections and about 2,115 words.
01Substrate Preparation and Evaluation
Large format tile (LFT), typically defined as tile with any edge longer than 15 inches, demands a substrate that is flat, sound, clean, and properly cured. The most common flatness standard for LFT is 1/8 inch in 10 feet (or 1/16 inch in 2 feet) when using a 1/2-inch notch trowel and a medium-bed mortar.
301 words, about 2 min02Materials, Mortars, and Adhesives
Large format tile requires mortars that can support the tile's weight and achieve full coverage. ANSI A118.4 (modified thinset) or A118.15 (improved modified) are typical; for LFT, a medium-bed mortar (ANSI A118.4TE or A118.15TE) is often specified because it can be applied up to 3/4 inch thick without slumping.
271 words, about 1 min03Layout and Planning
Proper layout prevents small cuts, minimizes waste, and ensures symmetry. For large format tile, layout is critical because the tile's size magnifies errors.
260 words, about 1 min04Installation Techniques for Large Format Tile
Installing LFT requires careful handling to avoid lippage and ensure full coverage. The key steps: apply mortar with the flat side of the trowel to key it into the substrate, then comb with the notched side in one direction.
244 words, about 1 min05Tile Leveling Systems and Lippage Control
Lippage is the difference in height between adjacent tiles. For LFT, lippage tolerance is typically 1/32 inch (0.8 mm) for grout joints less than 1/4 inch, and 1/16 inch for wider joints, per ANSI A108.02.
236 words, about 1 min06Movement Accommodation and Joint Design
All tile installations move due to thermal expansion, moisture changes, and structural deflection. Large format tile requires movement joints to prevent cracking and tenting.
214 words, about 1 min07Waterproofing and Wet Area Applications
Wet areas such as showers, steam rooms, and exterior installations require waterproofing to protect substrates and prevent mold. For LFT, waterproofing membranes (sheet or liquid) must be applied over a properly sloped substrate (1/4 inch per foot to drain).
215 words, about 1 min08Cutting, Tooling, and Equipment
Large format tile requires specialized cutting tools. A wet saw with a large table and a high-quality diamond blade is essential for straight cuts.
207 words, about 1 min09Safety, Codes, and Industry Standards
Tile installation is governed by ANSI standards (A108 series for installation, A118 for materials) and TCNA guidelines. Key standards: ANSI A108.02 (general requirements), A108.5 (dry-set mortar), A108.10 (grout), and A118.4 (modified mortar).
167 words, under 1 min