Plan the perfect garden with our interactive tool →

How to Lay Flagstone on Decomposed Granite

Flagstone is a type of natural stone that is commonly used as paving slabs for patios and floor surfaces. Flagstone provides natural beauty with an elegant, sophisticated look. Decomposed granite, composed of small pieces of granite, is a type of material used to help create a sturdy foundation when installing a flagstone patio without mortar. There are many benefits to this type of building material, such as the fact that it's normally less expensive and easier to use than mortar.

Step 1

Place a call to your city building department to see if there are any required building permits.

Step 2

Contact your utility company and have them mark off any areas with underground wiring where you're not allowed to dig.

Step 3

Measure the desired length and width of your patio and pound four wood stakes into the ground to denote your four borders. Run a piece of twine along the outside of the four pieces of wood.

Step 4

Excavate a hole within the borders of your area, approximately six inches deep, and level out the soil at the bottom.

Step 5

Install flexible edging around the inner border of your digging area by pounding posts into the ground to secure the edging.

Step 6

Dump a three-inch layer of decomposed granite onto the entire bottom surface of your dug-out area, and level out the decomposed granite until it's even.

  • Place a call to your city building department to see if there are any required building permits.
  • Excavate a hole within the borders of your area, approximately six inches deep, and level out the soil at the bottom.

Step 7

Compact the decomposed granite down tightly with a plate compactor, which can be rented from a store that sells building materials.

Step 8

Add a three-inch layer of sand on top of the decomposed granite and level it out by using a rake to smooth the surface.

Step 9

Lay your flagstones one at a time, starting in one of the corners. If you're using loose flagstones, leave around one inch of space between stones. If you're using flagstone pavers, leave 1/8 inch of space between stones.

Step 10

Fill in all cracks between the flagstones tightly with sand and spread the sand around with a broom.

Step 11

Sweep any sand off the surface of the stones, and the patio is ready to use.

  • Compact the decomposed granite down tightly with a plate compactor, which can be rented from a store that sells building materials.
  • If you're using loose flagstones, leave around one inch of space between stones.

Related Articles

How to Install Pavers for a Grill
How to Install Pavers for a Grill
How to Lay Brick Pavers With Mortar
How to Lay Brick Pavers With Mortar
How to Build Steps for My Back Door
How to Build Steps for My Back Door
How to Fix a Gap Between the Driveway & Garage
How to Fix a Gap Between the Driveway & Garage
How to Build the Column for a Front Gate
How to Build the Column for a Front Gate
How to Build a Bulkhead
How to Build a Bulkhead
How to Use Felling Wedges
How to Use Felling Wedges
How to Build a Rock Pillar
How to Build a Rock Pillar
How to Anchor a Garden Arch
How to Anchor a Garden Arch
How to Set Stone Pavers With Mortar
How to Set Stone Pavers With Mortar
How to Attach Paneling to Basement Walls
How to Attach Paneling to Basement Walls
How to Build a Foundation for a Carport
How to Build a Foundation for a Carport
How to Lay 24 by 24 Patio Stones
How to Lay 24 by 24 Patio Stones
How to Build a Brick Bench
How to Build a Brick Bench
How to Stabilize a Pergola
How to Stabilize a Pergola
Garden Guides
×