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Tuesday, September 30, 2014

Question

It is recommended to use floor sealer on Terrazzo that was installed 10 years ago. Why? What is the benefit? How many coats are recommended to be applied after the floors has been stripped before laying finish on it?


Answer

A floor seal on Terrazzo penetrates the porous part (Portland cement) of the matrix and helps prevent staining and discoloration. It also can help smooth a surface roughened by wear and the lack of finish.
See the seal manufacturer’s recommendation, but a couple of coats applied and properly dried before laying finish should be sufficient.
Here is a comment from the National Terrazzo and Mosaic Association, Inc.
www.ntma.com/care-maintenance.php
“DO seal your floors with a water-based acrylic sealer in accordance to the manufacturer’s instructions. Normally, a new floor requires two or more coats, which provide a good sheen for a period of 45 to 60 days, before needing additional coats. Sealer should be classified by Underwriters Laboratories, as slip resistant with a rating of minimum 0.5.”
Check the information at www.ntma.com/owners-guide.htm to learn of the different types of Terrazzo binders and what seals to use. Non-porous binders use non-penetrating seals.

Lynn E. Krafft, ICAN/ATEX Editor
lekrafft@juno.com