Decomposed granite begins life as granite rock. As it decomposes, it weathers into smaller pieces. The granite can be as small as a grain of sand or up to one-quarter inch in diameter. Decomposed granite is a good surface for walkways, driveways or as a well-drained surface in pet kennels. Using decomposed granite provides a natural look to any surface and many people are able to install it themselves.
Choose the right type of decomposed granite. Varieties include loose granite, decomposed granite with stabilizers and decomposed granite with resin. Loose decomposed granite is the least expensive choice and does not have anything mixed with it. Decomposed granite with stabilizers compacts a little more firmly, but still has a loose surface. Decomposed granite with resin has a hard surface when it is completed and looks and feels similar to asphalt. All three types of decomposed granite can be used for various projects, however the decomposed granite with stabilizers and resin, while more expensive, lasts longer.
Mark the construction area. Use wooden stakes and string to mark off the patio, driveway or other area you are building. Examine the project area carefully and make sure you are happy with the layout before you start your project.
Prepare the surface of the area where you plan to install the decomposed granite. The ground under the project area should be free of debris. Landscape-Design-Advice.com recommends laying 3 to 4 inches of gravel as a subsurface before adding the decomposed granite. This will improve drainage, which will lengthen the lifespan of the decomposed granite.
Fill the area with decomposed granite. Use a shovel and a wheelbarrow to evenly distribute the granite over the surface of the area, and follow up with a rake to smooth the granite. You should aim for 3 to 4 inches of granite, spread evenly across the entire project.
Compact the area using a commercial roller, hand tamper or vibrating plate tamper. These items are available for rental from commercial rental stores and make quick work of compacting the granite surface. Taking the time to compact the surface thoroughly will extend the lifespan of your project.