HOW TO CHOOSE A WET DRY VACUUM
Polymeric sand improves the durability of pavers and slabs. It contains a binding agent that helps to lock the pavers together. The pavers will not move or shift away from each other. When pavers shift, they create an uneven surface which spoils the aesthetics and could also be dangerous for people walking on the pavements. It will make them stronger and durable. Weeds are very common in areas where there are gaps between two pavers. Polymeric sand deters weeds thus ensuring that your patio remains in good condition. The product also ensures that sand in the joints is not washed away when there are heavy rains. It also reduces the amount of water that passes down into the base materials thus ensuring the foundation remains stable.
Another reason to use poly sand is that it prevents ants from coming up in the joints. Ants thrive where there are joints and this is why you see little hips of soil on pavements with joints. The product works well with all paver applications. It can be used even with natural stone.
Polymeric sand comes in different colors. You can get shades of gray and beige. Once cured, you can use a powered machine to clean your pavements.
Types of Polymeric sand: HP and RG
HP Polymeric Sand
HP sand is made from a mixture of graded sand and the latest generation of polymer binders. The sand is ideal for joints with a maximum width of 1 inch and a minimum depth of 1.25 inches. It is characterized by great durability, making it ideal for use in filling slab joints and pavers in highly-exposed areas such as public walkways that have heavy foot traffic, sloped driveways that are susceptible to run-offs that cause erosion, and pool decks that are frequently soaked. HP sand is also recommended for replacing wide joints where conventional sand had been used.
RG Polymeric Sand
RG sand is also made from a mixture of graded sand and polymer binders. RG polymer sand offers incredible weather resistance, making it ideal for situations where stabilization is required. RG sand is ideal for joints with a maximum width of half an inch and a minimum depth of 1.5 inches. It is recommended for the filling of slab joints and pavers on surfaces that are exposed to normal car and foot traffic such as terraces, driveways, access roads, garden paths, and backyards.
Polymeric Sand Application Checklist
- What is the weather going to be like? You should only install polymeric sand if the temperature will be above 32°F and if there is no forecasted precipitation for at least 3 hours (RG+) and 24 hours (HP) to ensure that the sand dries fully. The surface should also be perfectly dry before installation.
- Be prepared with equipment to do mechanical or manual compaction to remove voids and to create perfect contact between the aggregate, binders, and polymer, which leads to solid, durable joints.
- Using a broom and a leaf blower, remove all sand residue before misting the surface. This prevents the sticking of the sand of the surface of the slabs or pavers. Moisten the sand joints down to 1.5 inches.
- Ensure no water comes into contact with HP sand before it is completely dry, be it rain water or splashes. RG+ sand is weather-resistant 2 hours into wetting, but give it time to dry completely also so it can reach its maximum strength.
Wear protective clothing before installation. Test the sand on a small hidden area to determine if it meets your expectations.
The temperature should be above 32°F during the drying process, there should be no precipitation, and the surface must remain completely dry since this prevents moisture from activating the polymer, which would make the sand stick to the surface and cause stains.
Spread the sand uniformly over the surface using a push broom, ensuring that it fills the joints completely. Do not sweep the sand over long distances as this creates a screening effect that drags coarse particles and leaves behind the fine particles that contain the binders and the polymers.
Use a plate vibrator over the surface for pavers that are 2 inches or more, thick. For slabs and pavers that are 2 inches or less thick, hammering with a rubber mallet is sufficient (manufacturers discourage the use of mechanical compaction for thinner surfaces).
Repeat steps 1 and 2 until joints are filled up completely from the bottom (or at least 1/8 inch from the top).
Sweep the surface using a brush that has fine bristles and a leaf blower to remove all residues, keeping in mind the sand activates when in contact with water, sticking to the surface of the slabs or pavers.
Moisten the sand joints down to 1.5 inches using a fine mist – the bottom of the sand joint must remain dry. A fine mist prevents water from displacing the sand. Moisten the entire section continuously and lightly to prevent flooding and runoff. A screwdriver can help you verify the progress of wetness. Stop the watering once you hit 1.5 inches and move to the next section. Note too much water causes the binder to run off and prevents the sand from solidifying.
When wetting the surface, you shouldn’t spray more than 500 sq. ft. (HP) and 250 sq. ft. (RG+) of the surface at a time. This is because wetting a large surface at once takes too much time and the sand will start drying on the surface, making it difficult to moisten properly.
To ensure maximum cohesion after wetting, ensure no water comes into contact with HP sand before it is completely dry. Use a tarp if the surface is likely to be exposed to rain water or splashes during the drying period. RG+ sand is weather-resistant 2 hours into wetting, but give it time to dry completely also so it can reach its maximum strength. Keep in mind that polymeric sand, needs to dry completely to polymerize and to offer all its benefits, just like paint.
Motor vehicle areas should be given between 24 and 48 hours before use (after drying) while areas for residential use can be used immediately the sand is dry.