Essentially this is a man-made chemical binder or organic biner that binds the sand together and to create a single surface between the joints of the interlocking pavers. This glue holds the sand in place so that when it rains or running water, the water will not wash away the sand.
A light watering will activate a small amount of the sand but won't penetrate down deep enough to activate the entire joint. When this happens, a thin skin will be formed where the water did penetrate but all the sand beneath it will remain completely dry … and not activated at all!
Polymeric Sand has many benefits, however, the biggest drawback is that it can be easy to mess up, especially if you don't follow the manufacturer's instructions.
Initially, some water will seep into the joint sand for the first few weeks but soon silts and dust in the air will fill any voids and water will then shed off the paver surface just like any other pavement.
Remove the tarp as soon as the rain is done so the air can assist in the curing process since PolySweep needs to dry fully to be cured. A hard rain on polymeric sand that has not set up properly could result in sand all over the tops of the pavers.
If remov- ing polymeric sand, a hot water pressure washer will help to soften up the binders in the sand. Any tough to remove hardened areas, may require mechanical means to clean the joint. Take caution with natural stone or thin style pavers and be sure to avoid disturb- ance of the bedding sand underneath.
Polymeric sand is the most popular and useful filler used under brick pavers. It is a mixture of fine sand, adhesive and is most widely used in paver joints. Typically, polymeric sand lasts for up to 10 years. But if you use high-quality polymeric sand, it can last for approximately 15 years.
When looking for alternatives to polymeric sand, you will also want to find high quality materials. There are other products, such as EnviroSAND, EnviroSTONE and EnviroPATH on the market that are able to stop water erosion from occurring.
When properly installed polymeric sand is very weed resistant. There are many factors that can lead to early failure of the sand such as not getting sand deep enough into joints, applying too much OR to little water to activate, paver systems that hold too much moisture, hills, and a lot more.
Protect from rain for at least 12 hours. No sealer is required. Sand remaining on paver faces can create a slight haze after wetting. A minimum of 24 hours drying time is required prior to allowing significant foot traffic and 48 hours for vehicular traffic on the paver surface.
Polymeric sand cures by drying. And in order to fully set, it needs to dry out completely. If your polymeric sand didn't harden up, it's pretty much guaranteed there's a moisture issue. If the joints remain wet after the installation, they will remain soft until they dry.
Polymeric Sand works best when it is used to fill the entire depth of the paver. In addition, it works best on joints that are between ¼ inch and 1.5 inches wide.
To add to the cons of using polymeric sand, the bond it forms between each paver is incredibly rigid. This is ideal in a rigid paving system, but if your paver project has been set in a flexible system, using this sand can cause cracks and holes to form within the joints when the surface experiences heavy weights.
Moss. CasaScapes polymeric sand will not cause nor prevent moss, mold or mildew. Moss, mold and mildew are caused by certain on-site conditions including excess moisture, shade, absence of ventilation, inadequate cleaning or maintenance, presence of soil or other organic debris left on the product.
Epic Fail #1: Too much or too little watering.
Using too much water can cause the sand to wash out of the joints. On the contrary, using too little can result in the product not setting up properly. Hazing can also occur if sand residue isn't fully washed off the surface of the pavers.
sweep polymeric sand into a joint, there are pockets of air and spacing throughout the sand matrix. Proper compaction of the surface will tighten up the sand particles eliminating pockets of air and voids.
It is important to empty the joints before filling them up with Techniseal® Polymeric Sand. Polymeric Sand needs a minimum depth of 4 cm (1 ½”) to be effective.
The prep work is the most time consuming: you must have a clean, dry surface and joints. Unfortunately with polymeric sand replacement, you can't just uproot any weeds and top it up. You have to completely remove all the pre-existing sand in the joints and start fresh.
Polymeric sand hardens in place when exposed to moisture so the sand particles bond together and are more resistant to ants mining through it.
If your surface has a slope, start at the lower end and work your way up. Concentrate on small areas at a time (a good rule of thumb is 200 s.f. increments). Generally speaking, you'll want to perform three rounds of watering. The initial showering should be done at a height of about 4 ft.
Traditionally, concrete paver manufacturers have recommended waiting at least 90 days after polymeric sand installation to apply a protective sealant to a paver surface. Nowadays, a 30 day delay is sufficient to allow the evaporation of any remaining natural efflorescence contained in the pavers.
To maintain polymeric sand joints, keep a bag of this high-grade sand at hand so that you can use it whenever the need arises. You need to keep the package away from sunlight in a dry place. Do not take the sand out of its package unless you are applying it.