CTI Grout & Mortar Systems Flashcards

Which setting mortar has a peanut-butter consistency and is applied with a notched trowel to create bonding ridges?

Answer: Thinset mortar

Thinset mortar has a wet, spreadable consistency applied with a notched trowel; the ridges collapse when tile is pressed in, maximizing contact.

ANSI A118.4 specifies performance requirements for which type of tile setting mortar?

Answer: Latex-Portland cement (polymer-modified) mortar

ANSI A118.4 specifies requirements for latex-Portland cement (polymer-modified) mortar, offering improved bond strength and flexibility over standard thinset.

When inspecting large-format tile (24"×24" or larger) installations, what technique should a CTI inspector verify was used to achieve proper coverage?

Answer: Large-format mortar with back-buttering of tile back

Large-format tiles require medium-bed mortar and back-buttering to achieve the minimum 95% mortar contact coverage required by TCNA.

What minimum mortar contact coverage does TCNA require for tile installations in wet areas such as showers?

Answer: 95%

TCNA requires 95% mortar contact coverage in wet areas and exterior installations to prevent water infiltration and ensure structural integrity.

What product is the standard recommendation for removing dried cement grout haze from tile surfaces?

Answer: Sulfamic acid-based cleaner

Sulfamic acid cleaners dissolve dried cement grout haze without the aggressive strength of muriatic acid, making them safe for most tile surfaces.

What does a medium-bed mortar offer that standard thinset mortar cannot provide?

Answer: Application thickness up to 3/4 inch without slumping or shrinking

Medium-bed mortars contain anti-slump additives allowing greater application depths up to 3/4 inch to accommodate substrate variation under large tiles.