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Asked by: Astika Meyeroff
business and finance construction industryWhat is modified thinset mortar?
Considering this, is modified and fortified Thinset the same?
There are several terms, 'fortified, modified, latex, polymer', etc. These thinset mortar are either blended with dry latex in the bag, or mixed with an additive instead of water. This type of mortar has more strength, has flex, and is generally better than thinsets that are 'unmodified'.
Also question is, is modified thinset waterproof?
All portland based cementious products will allow water to pass through. The latex modified is more resistant due to the latex that is mixed in with the adhesive but that doesn;t make it "waterproof". The latex also allows a bit more flex in the tile and substrate. As Jason described, thinset itself isn't waterproof.
Modified thinset, on the other hand, is not recommended because it relies on air to cure properly. It's important to note that latex-modified thinset can still be used between the membrane and the subfloor because it is not impervious. However, unmodified thinset should be used between the membrane and the tile.