Last Updated on August 18, 2023 by Krystine
While polymeric sand offers benefits like preventing weed growth like weed killers when installed properly, it can deteriorate quickly and poses some environmental risks.
However, it is generally considered an eco-friendly product.
Read on to learn more about polymeric sand and its impacts.
Is Polymeric Sand Bad for the Environment?
Polymeric sand is considered an eco-friendly product that does not contain toxic chemicals or release hazardous compounds.
As long as proper installation guidelines are followed, polymeric sand is unlikely to cause substantial impacts on the environment or human health.
- The main ingredients are sand and inert silicate binders, no VOCs
- Does not leach dangerous chemicals when cured
- Poses minimal risks to nearby soils and waterways
- Safe for standard landfill disposal when spent
What Are the Main Ingredients in Polymeric Sand?
The main ingredients in polymeric sand are sand and additives like silicates, silicones, or silanes that provide binding properties.
A catalyst is used to activate the binding agent when wet.
Some versions also contain carbon black for UV resistance.
While the exact formulations vary by brand, polymeric sand does not contain toxic substances like solvents or VOCs.
The ingredients are considered safe and chemically inert.
Using polymeric sand as directed minimizes any likelihood of ecosystem contamination from compounds leaching.
Can Polymeric Sand Wash Out of Joints When It Rains?
Yes, heavy rain can wash out the binding agents in polymeric sand before it fully cures, causing it to erode out of paver joints.
This leads to weed growth in the joints, instability, and the need for reapplication.
To prevent washout, proper installation is key.
Joints must be completely dry and the sand actively wetted to activate the binder.
Avoid disturbing the sand before it sets.
Preventing rain exposure for 24 hours gives the best results.
But some washout in intense storms is still possible.
Does Polymeric Sand Contains Harmful VOCs?
No, polymeric sand does not contain volatile organic compounds (VOCs) or release any VOC emissions into the air.
This makes polymeric sand safe for use around people and pets immediately after installation.
Some older pavement joint sands used solvent-based binders that emitted VOCs as they cured.
But modern polymeric sand formulations utilize environmentally-friendly, water-based binders instead.
This eliminates VOC off-gassing issues while still providing binding properties when activated with water.
Can Polymeric Sand Contaminate Nearby Soil or Waterways?
Uncured polymeric sand that washes out of joints could theoretically contaminate nearby soil or waterways since it contains silicates.
However, any impacts once diluted would be very minimal.
Polymeric sand is designed to be non-toxic.
Proper installation and curing should prevent significant sand runoff.
The small amounts lost during occasional intense rains should not pose substantial environmental risks.
Using polymeric sand according to manufacturer guidelines ensures safe use.
Does Polymeric Sand Require Special Disposal?
No, polymeric sand does not require any special disposal considerations.
Since it contains only sand and inert binders, it is non-hazardous.
Standard landfill disposal is safe, or spilled sand can be directly reapplied.
While uncured polymeric sand should be prevented from washing into waterways due to silicates, once cured it is chemically stable and safe. As an environmentally-friendly product, polymeric sand can even be spread in gardens or composted. It does not contain any concerning chemicals or leachates.
Are There Any Serious Health Risks from Polymeric Sand?
When used properly, polymeric sand does not pose any serious health risks.
The main hazard is temporary skin or eye irritation from contact with abrasive sand particles, so protective equipment is recommended during installation.
However, polymeric sand is non-toxic when cured or if accidentally ingested.
Polymeric sand also does not contain respirable silica, unlike playbox sands, eliminating lung dangers.
While dermatitis could occur, uncured polymeric sand should not be handled extensively.
As with any construction product, standard safety practices minimize any risks when handling polymeric sand products.
What Are the Negatives of Polymeric Sand?
Some potential negatives of using polymeric sand include:
Deterioration and erosion over time, requiring reapplication
Weed growth if improperly installed and uncured sand washes out
Possible toxicity to vegetation if applied heavily onto plants
Runoff if intense rain occurs before the sand is cured
Lighter joint color that some find unappealing aesthetically
Loss of flexibility and permeability compared to basic sand
More expensive upfront cost versus traditional joint sand
Requires meticulous installation for proper binding and stabilization
However, when applied correctly per manufacturer instructions, most issues with performance, longevity, and environmental impact can be avoided.
Proper curing time is key for maximum durability and weed prevention.
Is Polymeric Sand Harmful to Plants?
Direct application of loose, uncured polymeric sand could potentially irritate or harm plant tissues.
However, normal use around properly installed pavers should not significantly impact mature adjacent plants.
Some online anecdotes report damage to nearby vegetation, but this is likely due to excessive application of foliage and immature plants.
Polymeric sand should be carefully swept off of leaves during installation to prevent toxicity. Once cured, leached binders in rainfall are heavily diluted and unlikely to impact vegetation.
What Happens to Polymeric Sand When It Rains?
When first installed, uncured polymeric sand can erode out of paver joint spaces if exposed to heavy rain before having time to properly settle and cure.
Water activates the binder but can also displace unsettled sand.
This leads to hollow joints prone to weed invasion and instability.
Preventing rain contact for 24 hours after wetting sand provides optimal results.
However, occasionally a sudden downpour can still displace sand before completely curing, requiring a reapplication.
Even after curing, intense storms may erode a small amount of sand over time.
Proper installation minimizes washout issues.
Is There Anything Better Than Polymeric Sand?
Some alternatives that can outperform polymeric sand include:
- Basic joint sand – More natural and flexible, but allows weeds. Requires more maintenance.
- Cement-based grout – Extremely stable and weed-free but at risk of cracking.
- Epoxy-bonded aggregate – Does not erode easily but is rigid.
- Compacted decomposed granite – Weed barrier and natural look, but requires refilling.
Polymeric sand strikes a good balance when properly mixed and installed.
It resists erosion and prevents weed growth fairly well compared to basic sand.
For most applications, polymeric sand is a popular, effective choice.
Overall, when installed correctly, polymeric sand is considered an environmentally-friendly product that does not contain toxic chemicals or poses substantial ecological risks.
Following manufacturer instructions for application and curing is important to gain the benefits while avoiding potential issues like washout or weed growth.
Frequently Asked Questions
Does polymeric sand contain silica?
Polymeric sand does not contain crystalline silica, unlike play sand and some joint sands. The silicates used as binders are amorphous silica, not dangerous respirable silica dust. This makes polymeric sand safer to handle and install.
How long does polymeric sand last?
When properly installed, polymeric sand typically lasts 2-5 years before requiring replacement. Harsh winters, intense rain, sand composition, and pavement type all impact longevity. Occasional reapplications will be needed, but polymeric sand lasts longer than basic joint sand.
Can polymeric sand stain pavers?
In some cases, polymeric sand can cause a residual stain or haze on paver surfaces. This is purely cosmetic and can often be cleaned with soap and water. Preventing contact with the paver face during installation helps avoid staining issues.
Does polymeric sand need to be sealed?
Sealing polymeric sand with a joint stabilizer is not strictly required but can extend the durability and further reduce erosion. Sealers provide extra protection from UV rays, rain, freezing, and thawing damage. Most manufacturers recommend applying a sealer after installation.
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