A.Tilesetter and author
Michael Byrne responds: No grout I ever used
or heard of contained a built-in sealer, and
although latex and epoxy grouts are somewhat more
stain resistant than regular Portland cement
grouts, a quality high-performance sealer should
always be applied — after the grout has
cured — to help reduce staining and to
make housekeeping easier.
White grout is never the best choice for any
tile installation intended for a heavy-use or food
service area, and without a sealer, it may turn
"antique" white or even gray. Bleach can sometimes
be used to remove stains from white grout, but it
will fade colored grout. Once grout has been
cleaned, it should be allowed to dry thoroughly,
then be protected with an appropriate sealer.
The first step in the cleaning process is to
identify the grout. Many grout manufacturers offer
lines of cleaning and sealing products that, when
used as a single-source system, can significantly
reduce fading and color change. If an after-market
sealer is used, I choose a manufacturer that
produces both a sealer and a cleaning preparation.
Some acid-based cleaners may require one or more
wash-rinse neutralizing cycles before a sealer can
be applied.
On new installations, I never use regular grout,
which is a mixture of Portland cement, sand, and
water. Instead, I replace the water with a liquid
latex or acrylic, and mix it with regular grout
powders (sanded or unsanded). If the latex
component is factory-added as a dried powder
— called polymer-modified grout —
water is the usual liquid component.
After the tiles are cleaned, and once the fresh
grout joints have begun to set up, I strike the
joints to produce a smoother grout surface. When
hard, cured, and protected with an impregnating
sealer, smooth-surface joints are significantly
easier to clean than joints whose surfaces are
rough or uneven. Striking fresh grout is one of the
secrets of easy maintenance for tile. Adding the
protection of a quality sealer makes this kind of
finish ideal for an installation whose appearance
is important.