Alliance Gator Dust is a bonding joint material for flagstone and natural stone with wide joints. It gives a soft-set patio or walkway firmer joints than plain decomposed granite. Like any joint product, it only works as well as the base underneath it. This guide covers the base Gator Dust needs, the general steps of a soft-set installation, and where to find the manufacturer's own videos. We stock Gator Dust, Gator Sand and DG Stabilizer in the yard.
The base: gravel, then sand
Gator Dust must have a gravel base 2 to 3 inches thick. Anna recommends adding 1 inch of sand over the gravel. The gravel carries the load and drains water. The sand gives you a layer to bed and level each stone.
Use flagstone 1 1/2 to 2 inches thick for this kind of soft-set installation. Thinner stone should be mortared over concrete. See the flagstone thickness guide.
Compact the gravel in thin layers rather than all at once. A plate compactor, which many equipment rental shops carry, makes the job faster and the base firmer. A well-built base keeps stones from settling unevenly and keeps joints from cracking.
General installation steps
These are the general steps for a soft-set flagstone patio with a bonded joint material. Always follow the product's own instructions for mixing, wetting and cure time.
- Mark the area and excavate deep enough for the base, the sand and the stone.
- Slope the subgrade slightly away from buildings so water drains.
- Spread the gravel base 2 to 3 inches thick and compact it well.
- Spread about 1 inch of sand and screed it smooth.
- Set each flagstone, tapping it down until it is firm and level with its neighbors.
- Sweep Gator Dust into the joints and compact it.
- Clean dust off the stone faces, then wet the joints as the instructions direct.
Watch the manufacturer's videos
Alliance publishes instructional videos for installing its products at alliancegator.com. Watch them before you start. They show the details of filling joints, cleaning the stone surface and wetting the product.
Read the full label before you open the bag. Products like this are sensitive to how much water is used and when, and following the directions closely is the surest way to firm, even joints.
Joint width and weather
Edges matter as well. A firm edge, such as bender board or a mortared border, keeps the base and the outer stones from spreading over time. We carry bender board and stakes.
- Wider joints use less stone, but heels can catch in them. Keep joints tighter where people entertain.
- Install in dry weather so the product can set as intended.
- Clean haze off the stone before wetting, since residue can dry onto the surface.
- Remember that soft-set joints should not be blasted with a pressure washer.
Get everything in one trip
We carry Gator Dust and other Alliance products, plus trowels, levels, brooms and gloves. Roundtree Rock & Gardening shares our yard and sells bulk gravel, sand and decomposed granite for the base. Browse our supplies, and call to check what is in the yard today.
If you are not sure which joint product fits your project, bring your measurements and joint width. We can walk you through Gator Dust, Gator Sand and DG Stabilizer and help you choose.