Ultraflex LFT

Premium, Large-and-Heavy-Tile Mortar with Polymer

Ultraflex LFT is a premium, non-sag, large-and-heavy-tile mortar and thin-set mortar designed for large-format and heavy tile and stone for interior/exterior floor, wall and countertop installations. This mortar has a high content of unique dry polymer, resulting in excellent adhesion to the substrate and tile. It is formulated with Easy Glide Technology™ for ease of application.

Technical Data Sheet

Available Colors

00 White
09 Gray


Which tile mortars are recommended for use over Mapelastic® AquaDefense?

MAPEI mortars for use over Mapelastic AquaDefense are: Ultraflex® LFT™, Ultraflex LFT Rapid, Ultraflex LHT®, Keraflex™ Plus, Ultraflex 1, Keraflex SG, Ultraflex LHT SG mixed with Keraply®, Adesilex™ P10 Mosaic & Glass Tile Mortar mixed with Keraply, MAPEI Ultralite™ Mortar and Kerapoxy® 410.

What is the right mortar for my tile size?

Cement thin-set mortars, such as MAPEI's Keraflex™ SG and Porcelain Tile Mortar, are good for tile up to 15" (38 cm) on any side. If your tile has any side longer than 15" (38 cm), you will need a large-format-tile (LFT) mortar, such as MAPEI's Keraflex Plus or Ultraflex® LFT™ .

Which mortar is best for exterior installations in harsh climates?

A two-component mortar, such as MAPEI's Ultraflex® LFT™ and Ultraflex LFT Rapid, is best for exterior installations in harsh climates, such as those with very hot summers, extreme freeze/thaw zones and seasonally heavy rainfall.

Can I use Premium Mortar with a radiant-heat flooring system?

MAPEI's Premium Mortar for tile and stone should not be used with radiant-heat flooring systems. Polymer-modified, cement-based mortars, such as MAPEI's Ultraflex® LFT™, are generally recommended for installing tile over radiant-heat systems. Refer to the written instructions of the radiant-heat manufacturer for recommendations of cement-based mortars.

Can Premium Mortar be used outside?

MAPEI's Premium Mortar for tile and stone should not be used for exterior installations. Polymer-modified, cement-based mortars that are generally recommended for installing tile outside include MAPEI's Ultraflex® LFT™ mortar, and MAPEI's Keraflor® mortar mixed with MAPEI's Keraply® additive.

Is a polymer-enriched mortar the same thing as a latex-modified mortar?

Yes, there are several terms used to describe a cement-based tile mortar that contains polymer, such as "latex-enriched," "latex-modified," "polymer-enriched" and "polymer-modified." MAPEI's Ultraflex® 1, Keraflex™ SG , Keraflex Plus , Ultraflex LFT™, MAPEI Ultralite™ Mortar and Adesilex™ P10 Mosiac & Glass Tile Mortar contain polymer and are considered modified.