Polymer Additive

Additive for Non-Polymer-Enriched and Select Mortars

MAPEI’s Polymer Additive is an acrylic latex admixture used to enhance the performance of dry-set mortars as well as Mosaic & Glass Tile Mortar. This highly recommended admixture enhances bond strength, flexural strength and freeze/thaw durability.


Technical Data Sheet

Safety Data Sheet

Available at:
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Which mortar is best for exterior installations in harsh climates?

A two-component mortar such as MAPEI's Uncoupling Membrane Mortar mixed with MAPEI's Polymer Additive is best for exterior installations in harsh climates such as those with very hot summers, extreme freeze/thaw zones and seasonally heavy rainfall.

What is the advantage of using a two-component mortar with a liquid additive?

Using a two-component mortar with a liquid additive results in a high-performing mortar. Liquid additives such as MAPEI's Polymer Additive – improve the overall performance of the mortar by increasing flexibility, enhancing bond strength and boosting moisture resistance.

What is the proper way to mix a two-component, cement-based mortar?

Be sure to follow the packaging instructions carefully when mixing. Keep the correct ratios of liquid additive to mortar powder, do not add water, and adhere to the mixing and resting times. Use a drill rather than mixing by hand. Do not add more liquid additive or add water if the product begins to thicken.

What trowel size should I use?

The trowel size is determined by the size of the tile being installed. Generally speaking, the smaller the tile, the smaller the trowel notches; the larger (or longer) the tile, the larger the trowel notches. Refer to the Lowe's mortar selection chart for more information.