In July of 2013, we wrote an article regarding the proper installation of polymeric sand. That article is reprinted below with minor updates. However, a major change is occurring in 2016. Major polymeric sand manufacturers have revised their formulas to reduce the risk of polymeric haze. Products with this new composition will begin to appear this spring and should be widely available by summer.
Nothing has changed in the proper installation and maintenance, the new formula simply reduces the probability of residual hazing and clean up.
Polymeric sand is used to fill joints between pavers, including concrete pavers, stone pavers and brick pavers. The fine sand is combined with additives, usually silica, and forms a binding agent after it’s mixed with water.
Using polymeric sand instead of plain sand has many benefits including:
- Prevents Washouts
- Offers Different Colors
- Improves Durability
- Prevents Weeds
Sometimes after installing polymeric sand you may experience a white haze. This is called a “polymeric haze.” It is sometimes caused by removing the dust from the surface of the pavers during sand installation. A leaf blower is a great tool to remove the dust. The haze can also be caused by not washing off the excess water which has been discolored by the polymeric chemicals. And it can be caused by under-wetting the joints during installation.
The newest versions of polymeric sand are “fast setting” and start repelling water after 90 minutes. They close the window on sensitivity to rain during initial drying time and polymer washout due to over-watering. It is important to wet these fast setting products using the “shower” mode instead of the “mist” mode to ensure the joints are sufficiently showered. If not sufficiently wet during installation, the polymeric sand will form a crust on the top leaving the lower sand dry and loose. The first heavy rain could wash off the crust and activate the dry polymers below creating a haze on the surface of the pavers.