Changes in Fabrication
Adding of polyester and epoxy coatings with fiberglass mats on the
back of the stone is a change in fabrication.
Instead of bonding the setting adhesives to the stone directly,
the setting materials are now bonding to other than the stone surface.
Portland cement including modified mortars will bond to stone surfaces.
Portland cement will not bond to polyester.
Portland cement will not bond to epoxy.
Portland cement will not bond to resins.
Portland cement will not bond to mastic.
Entire projects have failed due to lack of communication of changes
Epoxy will bond to polyester.
Epoxy will bond to epoxy.
Epoxy will bond to Portland cement.
Epoxy will bond to resins.
Epoxy will bond to mastic.
The theme here is Portland cement will not bond to epoxy or polyester
resins, and epoxy will bond to Portland cement.
The tile industry has not printed this information, with the exception
of a cartoon created by Donato Pompo, CTC, which was published in
Tile Industry News.
Broadcasting sand into resins or epoxy does not make the backside
of the stone compatible with Portland cement mortar.
If in doubt as to what will effectively bond to changes in fabrication,
we encourage you to work with your favorite adhesive manufacturer.
Send the stone to the adhesive manufacturer for testing in their
The adhesive manufacturer will confirm to you what setting material
will work best with altered natural stone surfaces.
This process includes thinking and working with agglomerate tiles
You, the importer, are liable for changes in fabrication.
You are responsible to educate installers of altered stone surfaces
which have occurred from changes in fabrication as to what workmanship
requirements are necessary in order to make the installation last
A good example would include Bob Young's articles on green marble.
Stones subject to curling and crowning require special attention
to setting materials that will not contribute to/or aggravate the
moisture sensitive stone.
is part of a series of articles on Stone Failures (Dec. 2000) by
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