Installation Guide
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Resources
• Sealing Granite
As a general rule, it is important to seal any product that has any percentage of water
absorption to protect the surface. This applies to all natural stones including granite;
however, the only stones that typically go unsealed are black granites. When used as
countertops or in wet applications, sealed black granites are known to show water
marks and rings when exposed to moisture or acids for extended periods of time. These
watermarks or etchings can be caused by a number of factors, the most common is a
reaction of the sealer being exposed to water for prolonged periods. The other reason
may be a reaction of the mineral on the surface of the stone to acids. When using dark
stones in wet applications, proper sealing and waterproofing methods must be observed
based on the scope of work.
• Slate for Exteriors
Certain colors of slate are not rated for exteriors, wet applications or applications in
freeze/thaw climates. Slates can swell when they absorb water and as a result may rust,
become muddy, brile or flake excessively. It is important to know where the slate is being
installed prior to purchasing. Quartzite, although it looks like slate, is a completely different
rock and is perfect for wet and exterior applications as well as freeze/thaw climates.
• Epoxy Mortars for Onyx, Marble and Sandstone
It is important to use epoxy based, solid seing adhesives and grouts when installing mesh,
resin, epoxy or fiberglass backed, stone to ensure proper adhesion. Stones requiring epoxy,
even if not mesh-backed include; green marbles, serpentine stone, black marbles and
some sandstones. These stones will typically warp or discolor from exposure to moisture
during the installation process when using a standard mortar.
• Use of Application Mortar Colors
Many light stones such as marble and limestone may react negatively to the ingredients
contained in gray mortars. It is highly recommended to use white mortar on light stones
and gray mortar for darker ones.
• Stone Lippage
The presence of lippage can be exaggerated by a number of factors: uneven subfloors,
laying tiles in a 50% brick joint offset, not back buering large format tiles, grout joint width
being too narrow and natural light sources making standard variances more noticeable.
Industry standards allow for a certain amount of lippage to be present based on various
factors. To eliminate lippage altogether, some stones may be altered by grinding and
refinishing the surface. This procedure is to be conducted by skilled professionals and is
only possible on select stones and finishes.
• Sanded Grout on Natural Stone
When installing polished stones or stones with a soer MOHS rating, it is highly
recommended to use un-sanded grout or equivalent to avoid scratching the surface of the
stone during installation. Follow the grout manufacturer’s recommendations based on the
specified grout joint width.
Code™ • White Wedge High 5”x6” (Wall)
Code™ • White Trapezoid 4”x9” (Floor)