Ultraflex LFT

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

Ultraflex LFT is a premium, nonsag, 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.