How often do you need to redo polymeric sand?
If you chose polymeric sand, even if exposed to the same circumstances as regular sand, it may last up to ten years (or more). Note that to increase durability, you can apply a sealer over pavers in both cases (polymeric and regular sand).
Polymeric sand relies on a chemical reaction to harden it into the joints between your paving stones. Once it hardens, it is permanent.
Overtime (usually around 5 years), the polymeric sand used in between the pavers (which helps lock them in place) will begin to break down.
Polymeric sand is designed to fill the gaps between pavers to keep them solidly in place, prevent weed growth, and allow for proper drainage from the patio.
CAN I USE POLYMERIC JOINTING SAND? Yes. If you are tired of sand erosion, weeds and ants on your pavers, Techniseal Polymeric Jointing Sand can be used to replace old sand in your joints. Simply remove the old sand completely and apply Techniseal Jointing Sand.
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.
Homeowners can opt for regular sand if they want something easier to work with that also makes adjustments easy. Natural sand is a more suitable option than polymeric sand for bedding. Also, it is excellent for people looking for a budget-friendly option.
Wait about 5 to 10 minutes allowing the water to soak in. It may take 3-4 proper waterings in order to fully activate the polymeric sand. Test for water depth by digging out some sand to make sure it is wet throughout most of the joint. Replace sand.
Over time, the sand in between paving stones will erode and begin to fade. For the DIY pathway, this means you will need to fix the pathway in as little as 1-2 years, depending on weather changes. Polymeric sand problems lead to the inability to replace any of the paving stones that have eroded or have damage.
The first thing you need to do is remove ALL of the existing sand down to the bottom of the paver. Polymeric sand works best when used at full depth. A pressure washer works well or you can get down on your hands and knees and use some sort of tool that will dislodge the sand.
Can weeds grow through polymeric sand?
When the polymers dry and cure, the sand between the joints gets quite hard and it cements the pavers together. Weeds won't grow between the joints and the sand doesn't wash away.
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.
Polymeric sand hardens quickly
However, you should NEVER install polymeric sand when it is raining! Rain activates the polymers before the sand is in the joints which will ruin your hardscape by producing a haze and adhering sand grains to the surface of the pavers.
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.
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 sands are designed to soften and re-heal.
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.
One bag of 50 lbs (22.7 kg) of this product will cover between 20 to 30 square feet (1.86 to 2.8 m2) if the joints are about 1" to 2" (2.54 to 5.08 cm) wide and the stones are about 2" to 2-1/2" (5.08 cm to 6.35 cm) thick.
This particular material exists specifically to provide a lasting bond between pavers. But unlike normal sand, the compound hardens very quickly when you expose it to moisture or water. Thus, you must remove polymeric sand from pavers' surface before you finish your project.
For narrow joint installations, one 22.7 kg bag can cover up to 11 m2 (120 sq. ft.) For wide joint installations, one 22.7 kg bag can cover up to 4 m2 (40 sq. ft.)
Can you add another layer of polymeric sand?
It is not ideal to add a thin layer of polymeric sand on top of what's already there for many reasons: the original sand can be old, of unknown condition, and/or dirty. The best approach would be to remove at least 1" of the jointing material and follow the steps for a new polymeric sand installation.