How to Build a Decomposed Granite Patio

Created when granite rock naturally decomposes over millions of years, decomposed granite is a less expensive paving alternative to stone or concrete for an attractive, efficient patio. It packs tightly to form an almost concrete-like surface while allowing water to penetrate through. Though it's most frequently used on pathways, as garden mulch and as a base for pavers, decomposed granite performs well as a casual patio. This flexible material is excellent for forming bends and curves like other loose materials, yet it firms nicely and lasts for many years when installed properly.

Decomposed granite forms a concrete-like patio.


Step 1

Have your decomposed granite premixed with the hardener or mix it yourself following the manufacturer's instructions.

Step 2

Measure and mark the perimeter for your patio, using the measuring tape and marking paint.

Step 3

Insert a wooden stake into each corner and tie masons string between them to establish the perimeter.

Step 4

Excavate the patio area at least 5 inches deep, using the standard shovel.

Step 5

Rake the area smooth and level with a slight slope, using a garden rake.

Step 6

Install the edging along the inside perimeter of the patio, keeping it in line with the masons string. Ensure that the pieces are level with each other, using the standard level and mallet to make adjustments.

Step 7

Pre-drill a pilot hole in wooden stakes, using the power drill and drill bit. Space the stakes every foot along the outside of the edging and drive each one below ground level, using the mallet.

Step 8

Secure the stakes to the edging with wood screws, using the power drill and Phillips-head screwdriver bit.

Step 9

Lay out the landscape fabric over the patio area, overlapping the sections by at least 6 inches.

Step 10

Apply 3 inches of gravel over the entire area, using the shovel. Compact the surface tightly, making at least three passes over the entire area, using the plate compactor.

Step 11

Apply a 1/2-inch layer of decomposed granite over the gravel layer. Sprinkle enough water over the top of the granite to keep it moist, using the garden hose.

Compact the surface firmly, using the plate compactor. Repeat the entire process, allowing each layer to dry for 8 hours, until you obtain at least a 2-inch layer of decomposed granite.