How to Build a Flagstone Patio With Dry Construction

An alternative to setting flagstone in mortar is setting the stone in a sand bed.

For many years, flagstone has been a popular choice when building a backyard patio. Not only does the stone offer a sleek and natural look, it is also quite durable. If you've resisted installing a stone patio because of the extra work involved with pouring mortar, there is an easier and cleaner way to install flagstones. If you want to have a dry installation for your flagstone patio, just set the stones in a sand bed. You will build the patio like any other patio project, but instead of setting the stones in mortar, they will rest comfortably in sand.

Things You'll Need

• Flagstones
• Tape measure
• Shovel
• Wooden stakes
• Twine
• Gravel
• Sand
• Landscape fabric
• 2-inch thick pieces of lumber
• Rubber mallet
• Straightedge
• Wood screed
• Garden hose
• Broom

Instructions

1. Measure out the patio to your desired dimensions. Then place a wooden stake in the ground to mark each corner of the patio. Connect each of these stakes with twine. All excavation will take place inside this roped-off area.

2. Use the shovel to dig up the entire area. The depth of the excavated area should be able to accommodate four inches of gravel and two inches of sand.

3. Pour four inches of gravel over the excavated area. Tamp down the gravel with a shovel to create a flat and even surface. If you are working in a large area, consider using a power tamper to flatten out the gravel area.

4. Cover the entire gravel area with a landscape fabric cut to fit. This fabric is optional, but is used to stop weeds that could grow below the surface and pop up between the flagstones. In order to cover the entire space, you will need to overlap the fabric. Roll the fabric over the surface and overlap the pieces by approximately six inches.

5. Put the two-inch thick piece of lumber on top of the landscape fabric. Then pour the sand over the entire area. Once the sand just covers the top of the piece of lumber, you will know that you have two inches of sand. Remove the piece of lumber and then lightly wet down the sand with a garden hose. Smooth out the wet sand by taking another piece of wood and using it as a screed.

6. Start deciding where you will place your flagstones. It is a good idea to do a dry run right next to the sand bed. Place the flagstones in the order you would like them to go and then transfer them over to the sand bed. You will duplicate your dry run on the sand bed.

7. Place a few flagstones at a time and then pound them into the sand with a rubber mallet. Be careful not to pound too hard. Use a straightedge to make sure that all of the nearby stones are even and level with each other.

8. With all of the flagstones in place and pounded into the sand, cover the patio again with a layer of sand. Use a broom to sweep the sand around and into the spaces between each stone. Use the garden hose again to lightly spray more water over the top of the area. Once the sand dries, add more dry sand and sweep again. Keep repeating the process until all of the stones are set and secure.

References

• "The Complete Guide to Patios: Plan, Build and Maintain"; Philip Schmidt; 2007
• "Start-To-Finish Patios"; Ortho; 2004