Use and Care Manual

Maintenance Guidelines for Concrete Paving Products
2 | P a g e
Joint Sand
During normal use, the sand-filled joints receive dirt from traffic on the
pavement. Dirt settles into the top of the joints, helping to hold the sand in
place. Installations exposed to driving winds or runoff, however, may lose
some joint sand that can be simply replenished with dry sand. If the
problem recurs, sealers will help hold the sand in the joints. These are
applied over the entire paver surface as a liquid and allowed to soak and
cure in the joints. Ask your concrete paver manufacturer or distributor
about these products and their application.
Preventing Weeds and Ants
Weeds can germinate between pavers from windblown seeds lodged in the
joints. They don’t grow from the bedding sand, base or soil. Weeds can be
removed by hand or with herbicides. Take care in using herbicides so that
adjacent vegetated areas are not damaged. Use biodegradable products
that won’t damage other vegetation or pollute water supplies when washed
from the pavement surface. Besides stabilizing the joint sand, sealers can
prevent seeds from germinating, and prevent ants from entering.
Efflorescence
Most paver producers add chemicals to the concrete that reduces the likelihood of efflorescence
occurring. In most cases, the additives prevent efflorescence. However,
completely eliminating the chance of efflorescence isn’t possible because
it’s a natural byproduct of hardened concrete.
Efflorescence is a white haze that may appear on the surface of pavers
sometime after installation. It forms because of a natural chemical reaction
that occurs when the lime or water soluble calcium oxide produced by the
cement contained in the pavers reacts with water. When the water enters
the microscopic capillaries in the pavers calcium hydroxide is formed. The
calcium hydroxide rises to the surface of the paver, reacts with the carbon
dioxide in the air, and forms a white haze of calcium carbonate when the
moisture
on the surface of the pavers evaporates. The appearance of efflorescence
will stop when there isn’t any more calcium hydroxide available to move to the surface.
Since efflorescence brings out salts that are not ordinarily part of the paver, it is not a structural, but,
rather, an aesthetic concern. The white haze may give the impression that the color of the pavers is
fading but this is not the case. Efflorescence may occur randomly or be concentrated in certain areas.
Dark colored pavers show efflorescence more than lighter-colored ones.