Why size matters when it comes to gravel for a driveway

Why size matters when it comes to gravel for a driveway

At first glance, to many people, gravel is gravel—a bunch of small, irregularly shaped rocks used for roads, gardening and landscape projects, construction, and driveways. Planning on creating a new gravel driveway for your property out in the country or even suburban or city location? It’s more than just dumping a truckload and spreading it out; in fact, professional contractors use a blend of different sizes in order to construct a quality, efficient surface that drains well and stays in place. The last thing you want is the regular chore of corralling all kinds of stray gravel and putting it back in place.

Gravel is a popular driveway material choice for its affordability and low maintenance factor.  Keep in mind, however, that proper construction requires a blend of three different gravel sizes. Let’s look closer at this trio and their parts in the show.

Base layer

A commonly used gravel size for driveway base layers is #3 gravel. This rock is generally 1-2 inches in diameter and does double duty by establishing a solid, reliable foundation and providing adequate drainage; both critical factors in driveway construction. #3 gravel is crushed in giant machines and the final product is typically irregular shapes. #4 stone is also commonly used for base layers. This category of stone comes in golf-ball size and is usually mixed with sand. Some popular varieties include recycled, quarry, gray, and bluestone. A four-inch layer of #3 or #4 sets the stage for the second act.

Middle layer

Also about the size of a golf ball, a gravel driveway’s middle layer is made of crushed stone known as #57. This stone type creates an ideal substrate that promotes efficient drainage.

Icing on the cake

The top layer of a gravel driveway is what everyone sees, walks and drives on. This layer is made of “fines,” a blend of small gravel stones and rock dust. The stones and dust gradually fit together and form a tightly bonded surface that holds up to years of everyday use. Fines come in various colors as well, allowing you to tailor the driveway’s look to match the house and other nearby hardscapes.

Remember, a professionally installed gravel driveway looks great and will provide a reliable surface for the heavy weight of cars. Be sure to fully compact each layer to ensure settling and avoid gaps where the different gravel layers can intermingle and compromise the surface’s overall integrity.