High Performance Polymeric Sand For Concrete Paver, Wetcast & Natural Stone Joints up to 1″


Flexlock Sand is a unique mixture of polymer binders and calibrated sand available in Sandy Beige, Graphite Grey, Ivory & Onyx Black. The installation of Flexlock Sand is almost identical to using regular paver joint sand except for the application of water. Once Flexlock Sand sets, it becomes very firm and locks between the paver joints while still retaining flexibility and providing a long lasting, durable jointing material. Flexlock Sand is recommended for a variety of uses including pool decks, patios, footpaths, driveways, parking spaces, pavements etc.


  • Can be used for joints up to a maximum of 1 inch (2.5 cm) and its fine gradation allows use in even the tightest joints
  • Helps prevent weeds and damage caused by burrowing insects
  • Helps prevent erosion due to wind, rain, and freeze thaw cycles
  • Fast setting: Product sets within one hour after application of water
  • Sets at above freezing temperatures (32°F/ 0°C)
  • Can be applied even if rain is expected (however, minimum of 1 hour of dry weather is needed after activation)
  • Advanced Haze Free Technology
  • Intact pallets can be stored outside

Helps Prevent

Helps prevent weed sprouting.
Helps prevent damages caused by insects.
Helps prevent erosion due to climatic conditions, such as wind, rain and freezing.


Quantity required depends on the shape and size of the concrete pavers as well as the width of the joints.

Product Narrow Joints Wide Joints
  m2 | ft2 m2 | ft2
50 lbs (22.7 kg) 6.00-7.4 | 65-85 2.0-3.9 | 22-42


Product Retail Size Units per Pallets
Flexlock Sand 22.7 kg (50 lbs) 56 bags

- Plastic bags

- Intact pallets can be stored outside


Flexlock Sand is recommended for a variety of uses including pool decks, patios, footpaths, driveways, parking spaces, pavements etc. The concrete pavers must be installed on a drainage base system composed of 2 layers. The upper layer can have a maximum of 1 inch (2.5 cm) of bedding sand. The lower layer must have a minimum of 6 inches (15.4 cm) of crushed stone compacted at 98 % Proctor density. (See diagram below).


view image


Please note that this limited warranty applies when the product is used for residential purposes exclusively (home owners or contractors using the product for single or multi-unit dwellings that are exclusively for residential use). The manufacturer cannot guarantee results, as it has no control over surface and sub-surface preparation and product application. (Proper installation of pavers or slabs to ensure long-term stability of work, including granular foundation* of certified crushed stone of 0-3/4 inch (0-20 mm) bedding layer and appropriate installation of borders in accordance with above specified method for applying product). However, for a period of 15 years from purchase, the manufacturer agrees to refund the purchase price, if the product is proven to be defective, and on the condition that it was installed pursuant to the method of application of surface and sub-surface preparation described above, Proof of purchase is required for any claim.



Alliance Gator excludes any responsibility for the presence of moss, mold, mildew, or similar factors that may occur on the product after its installation. Alliance Gator excludes any responsibility for use of Flexlock Sand with Clay Pavers or any installation not installed to manufacturer’s specifications and ICPI Tech Spec #2.

* ICPI Tech Spec #2 ( Construction of Interlocking Concrete Pavements)


  • Pavers and slabs must be installed according to ICPI Tech Spec #2 ( before Flexlock Sand installation. If pavers are installed over a concrete slab, (overlay application) Flexlock Ultra Sand must be used.
  • Flexlock Sand Technical Data Sheet is available at:
  • Pavers’ sides and top surfaces must be completely dry. Do not apply if the paver surface is damp or wet. The damp or wet surface will cause Flexlock Sand to prematurely activate and will lead to the polymers sticking on the paver surface.
  • Do not apply if the paver joints are damp or wet. This will prevent the Flexlock Sand from properly sliding into the joints and obtaining very densely packed joints, which is critical to the products performance.
  • Temperature must be above 32°F with dry conditions (no rain for at least 1 hour) before installing Flexlock Sand.
  • Avoid excessive watering or flooding of paver surface.
  • For all paver surfaces, and particularly around in-ground pools there must be a slope of 1/8 inch (0.3 cm) per linear foot away from the edge of the pool, or structures to ensure optimal performance of the Flexlock Sand.
  • For the pool coping units it is mandatory to use mortar in the joints. For the rest of the paver installation around the pool, you can use Flexlock Sand.
  • Do not sweep Flexlock Sand over asphalt.
  • Install Flexlock Sand a minimum of 1/8 inch (0.3 cm) below the paver surface or erosion may occur. The filled and cured v joints should never be in direct contact with foot traffic or tires. The product must only be used as a recessed jointing material.


Step 1

Step 1

Spread Flexlock Sand with hard-bristle broom. Make sure the Flexlock Sand completely fills the joints. Do not use other materials in the joints.

Step 2

Step 2

Leave a layer of Flexlock Sand on the surface to aid in vibrating and consolidating Flexlock Sand into joints.

Step 3

Step 3

Vibrate the Flexlock Sand into the paver joints using a vibratory plate compactor. A rubber pad is recommended. A roller compactor is best for slab installation.

Step 4

Step 4

Joints should be filled up to 1/8 inch below the edge or chamfer. It is best to compact in several directions to ensure there are no air gaps or voids in the joints. Repeat steps 1-3 to ensure joints are filled and consolidated. Narrow joints require more care to completely fill.

Step 5

Step 5

Sweep off excess Flexlock Sand from the paved surface, first with a hard-bristle broom, then a soft bristle broom. Take care to leave the height of the polymeric sand at least 1/8 inch below the edge or chamfer of the paver.

Step 6

Step 6

Use a leaf blower to remove all remaining Flexlock Sand residue from the paved surface.

WATER ACTIVATION (Important Notes)

  • Work in manageable sections, ideally about 100 sq. ft. at a time, depending on temperature.
  • Do not allow Flexlock Sand to wash out of joint.
  • Never allow paved surface to dry out during the water activation phase.
  • Watering must be started at the lowest point of the paved surface.
  • Use a watering gun connected to a hose. Setting should be set to shower.

Step 7

Step 7

Shower water on a specific water area of 100 sq.ft., wait no longer than 2 to 3 minutes. Proceed to STEP 8.

Step 8

Step 8

Shower and rinse simultaneously on a section of approximately 100 sq. ft. so as to eliminate any Flexlock Sand residue left on the pavers. Any Flexlock Sand residue should go directly into the paver joints. Wait no longer than 2 to 3 minutes. Proceed to STEP 9.

Step 9

Step 9

Shower and rinse simultaneously, so as to eliminate any Flexlock Sand residue. Any residue should go directly into the paver joints. However, stop showering when you see water retention on the paver joints. Wait no longer than 2 to 3 minutes. Proceed to STEP 10. Note: Repeat the directions of steps 7 to 9 for all other areas that have not been showered with water.

Step 10

Step 10

Use a leaf blower to remove any excess water remaining on the paver pores and crevices. This blowing action is necessary to help remove any remaining Flexlock Sand residue left on paver surfaces from the previous steps.


If used on clay pavers make sure they are 100% dry. Clay pavers tend to hold moisture, which can prematurely activate the Flexlock Sand while the sand is being spread over the paver surface, leaving a residue (always apply on a test area before using the Flexlock Sand on clay pavers).


Flexlock 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.


The water used in steps 7 to 9 will activate a bonding action as well as condensing Flexlock Sand in the joints. It is important to water the Flexlock Sand a total of 3 times, as per steps 7, 8 and 9.Too little water will not properly activate the Flexlock Sand and will reduce the final performance. If steps 7 to 10 are not done properly, a white haze may appear on paver surface after installation. This is due to excess Flexlock Sand residue left on paver surfaces. This haze will dissipate over time, or it could be removed by using Flexlock Efflorescence Cleaner.

METHOD for applying Flex Lock Sand as part of an EXISTING PAVER JOB:


If using Flexlock Sand to replace existing jointing materials, old jointing materials need to be completely cleaned out of the joints and pavers completely dry before installing Flexlock Sand. However, be careful not to disturb the bedding material under the pavers. Follow steps 1 to 10 of Flexlock Sand installation steps (for a new paver surface).

Please Note

Do not apply on wet or damp surface since bonding action will cause Flex Lock Sand to stick on surface and prevent proper sliding in joint. Do not use if rain is expected within 1 hour. Avoid excessive watering or flooding of paved surfaces. When installing pavers around an underground pool, a 1/8 inch slope per linear foot from the pool is mandatory. All paver surfaces must have a drainage slope for the Flex Lock Sand to work at its optimum. For the pool coping units it is mandatory to use mortar in the joints. For the rest of the paver installation around the pool, you can use Flex Lock Sand.

-The Flex Lock Sand is ideal for narrow or large joints up to a maximum of 1″.
-Never use Flex Lock Sand when pavers are installed on a concrete slab. Over concrete slab the Flexlock Ultra is the recommended choice.
- Do not sweep over asphalt.

1Hr Setting Time at 32°F

Flex Lock Sand is the only polymeric sand manufacturer that provides a one-hour setting time warranty. Other polymeric sands require you to come back the following day to finish your work, and potential rainfall during the same day as the sand´s application would normally wash out the sand from the paver joints. But with Flex Lock, you will be able to collect your dues earlier for work done better and sooner.

Also, who else in the polymeric sand industry but Flex Lock enables you to perform this work at any temperature above 0°C (32°F), start your season earlier and extend it at least two months? With the competition, you have to wait for Mother Nature to give you a comfortable 15°C (59°F), you get two months less work time and a lower profit margin.

Additional information on our polymeric Sand.

  Flexlock Sand: TDS