The ideal time to install an epoxy joint sealant
is before the new concrete floor is put into service, thereby
preventing contamination of the joint. Epoxy joint sealants (Prime
Seal 5000) provide good expansion properties, which makes
them a good choice for a newly poured concrete slab. Most contraction
and expansion in a newly poured slab will occur early in its life,
before it stabilizes to its final volume. Exceptions to this are
in extremely cold environments, which can cause even old concrete
to shrink substantially.
Another reason epoxy sealants are ideal for new
construction is that they are typically moisture insensitive.
Good adhesion can be obtained even if the concrete is slightly
damp.
For best results, allow the concrete to cure
for 60-90 days and maintain the temperature of the facility at
its operating temperature for at least one week before the joint
sealant is installed. This will insure that the concrete has contracted
and the joint width has stabilized as much as possible. At a minimum,
the concrete should be 28 days old.
Generally, epoxy sealants are a great product
for new concrete construction, but it is an accepted fact that
most slabs will need some minor repair within one year of being
poured. Epoxy sealants are a good start but may need to be replaced
at some point in the future due to the dynamic nature of concrete
and the typical servicing requirements of the average industrial
or warehouse floor.
LIMITATIONS
Prime Resins Prime Seal products should not be
used for exterior applications. Joint seal epoxy becomes rigid
at temperatures below 40° F (5° C) and will not maintain
its bond as the concrete contracts. In addition, sunlight causes
epoxy to chalk and yellow. While this does not affect the performance
of the material, it is usually not aesthetically pleasing.
SLOPED FLOORS / RAMPS
Sloped floors may be sealed using Prime
Seal 5000 Caulk Grade. The caulk grade offers all of
the physical properties of the self-leveling material, but with
a thicker consistency that will not run.
JOINTS OVER ½” WIDE
If the joints are over ½” wide,
prime the sides of the joints with neat joint fill material. Then
mix 2-3 parts oven dried aggregate (Prime Blend Sand) with the
epoxy. The mortar can then be poured and trowel compacted into
the joint. The color of the epoxy mortar will be slightly lighter
than the neat material.
RANDOM CRACKS
Random cracks in floors may be repaired using
neat Prime Seal 5000. Route the cracks out to a depth of at least
¾” (one inch is preferred). Clean the dust out of
cracks and follow the instructions for neat epoxy joint sealant.
