HOW MUCH STONE IS ENOUGH?

MANEL PAVING & SEALING, CORP.

For all your residential and commercial paving

2” 4” 6” 8” HOW MUCH IS ENOUGH?

The question always comes up about how much stone is enough to provide the proper support for an asphalt driveway. We feel that 8” is the proper amount for our area, for the following reason:

In our area there are many towns and locations in which there is a great deal of clay sub-soil. For example; the Towns of Greece, Henrietta, Brockport, anywhere within the city of Rochester limits, and parts of Irondequoit have heavy concentrations of clay. Several towns actually have a shale layer about 5 or 6 fee below the soil which makes it very hard for any water to drain away from the clay sub-soil.

In order for a driveway to maintain it’s stability and integrity it must be built properly to allow for water that may permeate the surface to drain towards the drain away. The driveway needs to have the proper subsoil, sandy and loamy, which allows for quick drainage of any water. It must have the proper amount of stone base which allows for the water to drain from the asphalt surface, and the asphalt surface must be thick enough to support traffic. Depending what type of traffic, heavier like pick-ups trucks or vans, psi created by weight. Even with the proper stone and asphalt, the clay surface can be very detrimental to a driveway. Clay will absorb water in the spring and fall and create a very spongy, unstable surface. If there is not a proper amount of stone over the clay to cushion the asphalt and drain away the water, the resulting situation will be cracked asphalt. Once the asphalt has cracked it looses its structural strength and allows water to permeate it even more to effect the clay subsoil.

Unless you are in a real sandy soil, we recommend at least 8” of stone for your driveway for the reason mentioned above. There are situations where if you already have stone in your driveway (4” to 5”) and depending on the elevations required you may be able to add several inches of stone to achieve your 8” base. There are however, those situations where the elevations will not warrant adding more stone, and at that point it will make the driveway too high and you will not be able to open doors, and the water could drain into the garage.