Installation Guide

Product Information | 5
CONCRETE UNDERLAYMENTS AND
SUBFLOORS
• See Grade Levels below. All concrete
underlayments require moisture testing.
Grade Levels:
1. Suspended: An acceptable suspended
oor is a concrete or wood substrate with a
minimum of 18” (460mm) of well-ventilated
air space beneath it. Lucida Surfaces
recommends that a moisture vapor barrier
be placed on the ground below the air
space.
2. On-Grade: An acceptable on-grade oor
is a concrete substrate in direct surface
contact with the ground at the surrounding
ground level.
3. Below-Grade: An acceptable below-grade
oor is a concrete substrate partially or
completely in contact with the ground below
the average surrounding ground level.
• Concrete suboors must be dry, smooth and
free from dust, solvent, paint, wax, grease,
oil, asphalt sealing compounds and other
extraneous materials. The surface must be
hard and dense, and free from powder or
aking.
• New concrete slabs must be thoroughly
dry (at least six weeks) and completely
cured. Curing agents, surface hardeners
and other additives may cause adhesive
bonding failure. These should be removed
by sanding or grinding.
• All concrete slabs must be checked for
moisture before installing material. The
nal responsibility for determining if the
concrete is dry enough for installation
of the ooring lies with the oor covering
installer. Commercial glue down LVT must
never be installed where excessive moisture
emissions may exist. Moisture emission
from suboor cannot exceed 3 lbs. per
1,000 sq. ft. per 24 hours as measured with
the calcium chloride test. A result of up to
85% is acceptable per ASTM F2170. Lucida
Surfaces will not assume responsibility for
oorcovering failure due to hydrostatic
pressure or moisture vapor emission.
• Holes, grooves, expansion joints and other
depressions must be lled and troweled
smooth and feathered even with the
surrounding surface.
• Concrete oors with a radiant heating
system are satisfactory, provided the
temperature of the oor does not exceed
85°F at any point. The heating system
should be turned on to eliminate residual
moisture.
OTHER ACCEPTABLE UNDERLAYMENTS
• VCT (well bonded, on and above grade – in
absence of waxes or sealers)
• Ceramic (well bonded & properly prepared)
• Terrazzo (well bonded & properly prepared)
• Self-leveling and patching compounds (latex
fortied Portland cement based only)
• Resilient oor (no more than 1 layer, well
bonded, non-cushioned & properly prepared)
DO NOT INSTALL OVER
• Any type of carpet.
• Existing cushion-backed vinyl ooring.
• Floating oor of any type, loose lay, and
perimeter-fastened sheet vinyl.
• Laminate ooring.
• Cork ooring.