- Q.We are converting a
restaurant kitchen into an office and need to install
carpet over existing 6x6-inch ceramic tiles with
1/4-inch grout lines. The floor dips 3/4 inch near the
floor drain. What product can we use to level this
floor in preparation for a pad and carpet?
TechNet professional at the Floor Covering
Installation Contractors Association,
responds: Before proceeding, verify that the
moisture level of the substrate is not excessive.
Remove any loose tiles or grout, and cap the drain.
Clean the tiles to remove any grease, wax, or
coatings that might interfere with adhesion. Then
install a Portland-cement-based self-leveling
underlayment, following the manufacturer’s
recommendations. Self-leveling underlayments are
available from Ardex (724/857-6400; www.ardex.com)
and Mapei (888/300-4422; www.mapei.com).
Once the floor is leveled, cured, and sealed,
the carpet can be installed. If you want to include
a pad, you have two options: either use
"double-glue cushion" — a type of pad that
can be glued to both the substrate and the carpet
— or install carpet with an attached
cushion backing. Do not nail tack-strip into the
hardened leveling compound unless you are sure it
is at least 3/4 inch thick, since nails can shatter
the compound where it is thin.