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.
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.
Most poly sands are considered “rain proof” after one hour, but I wouldn't bet the bank on that. You really want at least 24 hours of warm, dry air to ensure that the poly sand completely sets. Sustained dampness prior to setting may damage the poly sand to the point it will never set.
Installing polymeric sand on a damp or wet surface could cause the sand and polymers to stick to the surface and become difficult to remove. After installation, a hard rain on polymeric sand that has not fully set up could result in polymeric sand all over the top of the pavers.
As stated, polymeric sand will harden on contact with water. It will create a layer over the pavers' surface, very difficult for you to remove in some cases. If the haze on the paver's surface is thin, you are likely to be able to wash it off with hose water.
First, you run the danger of disturbing your base/shifting your pavers. Secondly, you will have to wait a day while the surface dries before you can reapply your new sand. Remember polymeric sand and moisture don't mix until after it's in the joints!
UNDER-WATERING causes the polymeric sand to simply form a "crust" on the top. If you only have a crust, you don't have a proper bond in the joints. Eventually, the crust will break away, eroding the joint. It also causes cracks and gaps, because the sand hasn't fully bonded the entire depth of the joint.
When watering in the Poly Sand, remember Goldilocks - "This is just right." Don't use too much or too little water. The amount of water you use is a critical element to an installation. Using too much water can cause the joint to over-saturate and result in polymer washout, mushy sand, and a weak bond.
Polymeric sand can last up to 10 years before replacement is necessary. However, certain manufacturers claim some products can last up to 15 years.
Removing polymeric sand from pavers is not a fun process. You can try to use a hot pressure washer to remove the sand, but you may be left with some sand remaining in the joint. Regardless, you are going to have to scrape out the sand of the joints and use a shop vac or blower to remove this scraped out sand.
Epic Fail #1: Too much or too little watering.
A polymeric sand installation requires the use of a controlled and methodical watering technique. 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.
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.
Polymeric Sand can be used in pavers with false joints that are at least ¼” deep and ¼” wide. Specialized products such as TechniSeal SmartSand are designed for these applications. However, special care must be taken while cleaning off excess dust from pavers, especially if a leaf blower is used.
If us- ing polymeric sand, you can install it after the sealer application has properly cured for 24 - 48 hours. If polymeric sand is installed prior to sealing, be sure surface is dry for 24 hours before applying sealer.
You'll also want to check that thermometer because polymeric sand should be installed at a temperature of 32∘F or above.
If poly sand haze has transpired on the surface, it must be cleaned with an acid-based cleaner. Sometimes vinegar can be used unless the poly sand haze is severe.
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.
Gator Dust requires 24 hours on a conventional drainage base, it is not for use on overlays. Can I use regular sand to fill up half the joint and place Alliance Gator Polymeric Sand on top?
Avoid contact with moisture as it hardens very quickly when interacting with water. A soft-bristled broom should do the job; sweep away as much polymeric sand as you can. Use a leaf blower to get rid of the rest. But be sure not to blow away any polymeric sand from in between the pavers.
The amount of sand you use can make or break your paver installation, so it's best that you use no more than the recommended 1 inch. Here's why: A sand layer that is too thick can create waves in your patio during the installation. Pressing pavers into a thick sand bed may result in misalignment and a messy look.
Turn on your water hose and spray the sand using a gentle mist. Wet the filler evenly until the sand is compact and fully saturated. Allow the sand to dry for 24 hours.
Sweep the polymeric joint sand into the cracks between the pavers as you would with other materials. It is recommended that you do this three times to ensure that all of the joints are properly topped off. This will increase weed, insect and water protection.