Backyard flagstone patio with furniture

How to Build a Flagstone Patio

Build a flagstone patio to create a welcoming outdoor living space in your backyard. Flagstone pieces fit together to form a solid platform that is both durable and attractive.

A flagstone patio can become the base for a variety of uses. Place outdoor furniture on top of the patio to enjoy al fresco dining. Add lounge chairs and savor your morning coffee in the fresh air. Install a fire pit surrounded by cushioned benches to experience atmospheric evenings under the night sky.

The possibilities are endless, but first you’ll need to lay the groundwork by building a flagstone patio. This step-by-step guide will cover how to build a “dry” or “sand-set” patio rather than a permanent, wet-set flagstone patio.


flagstone patio with fireplace and plants
flagstone patio with rock wall and garden

Before you start building your flagstone patio

  • Choose your patio location. It’s best if your patio area is located away from trees or bushes. Plants can intrude on the patio over time.
  • Decide on the size, shape, and design of your flagstone patio. Mark out the border with spray paint.
  • Measure the overall square footage of the patio area in order to calculate the amount of landscaping materials you’ll need.

When you’re ready to build your patio, here’s what to do:

Flagstone Patio Pro Tip:

It’s best if your flagstone patio area is located away from trees or bushes. Plants can intrude on the patio over time.

10 Steps to a DIY Flagstone Patio

  1. Dig down about 6 inches across the planned patio area, removing dirt and debris. You must create enough space for the base layer material and for the stones. This ensures the patio surface will be level with the ground around it. Calculate the exact depth you need to excavate by adding the thickness of your flagstone pieces (usually about 4 inches) to the depth of sand you’ll be using as a base. We recommend 2 inches of sand base material.
  2. Level, smooth and compact the area. This alleviates excess water pooling and drainage issues. Tip: Wet the soil to make it easier to compact.
  3. Cover the area with weed barrier landscape fabric. This will help prevent weeds from growing up through the patio. It also stops the flagstones from settling and sinking too far into the ground.
  4. Spread approximately 2 inches of washed sand over the weed barrier fabric.
  5. Level the sand with a wood stud or leveling tool.
  6. Lightly mist the sand with water to make it firm.
  7. Lay the flagstone pieces out on the sand. Move and arrange the pieces until they fit together like a jigsaw puzzle. Place the stones roughly the same distance from one another, no more than 1 inch apart. If you need to cut the stone, use a chisel and hammer to carefully chip a notch on the spot where you want the stone to break. Cut only a small depth with each stroke. Use tools with caution and wear protective eye gear.
  8. Add or remove sand as needed to make a level surface.
  9. Push the stones down into the sand, keeping the surface level and even.
  10. Fill the gaps between stones with sand, pebbles or limestone screenings and wet thoroughly.
Fitting flagstone patio pieces together

What to do after you’ve built your flagstone patio

Now that you’ve built your own flagstone patio, you’re ready to add outdoor furniture on top of it. You might also want to consider connecting your patio to other areas of your yard. One way to do this is to add stepping stone paths. You can choose flagstone pieces that match your patio, or go with a different color of stone for contrast. Another popular DIY option is to build a decomposed granite pathway. Either way, you’ll want to have good access to your patio so it’s easy to step outside and enjoy your hard work.

Flagstone patio in backyard with furniture and crushed rock
Flagstone patio with potted plants and dining set