You build a lasting driveway in layers, from the native soil to the surface. Done right, these layers keep your driveway solid. At the bottom, excavation removes the soft earth down to native soil. On top of that, you spread and compact a crushed stone base. At the top comes the surface you see, in asphalt, interlocking pavers or concrete. National Asphalte builds these layers.
The native soil carries all the layers
The native soil is the ground already in place, under the topsoil. In the end, it takes the weight of every car. It has to be firm and free of anything that rots. Soft or wet soil shifts as it freezes and thaws. On weak soil, a layer of fabric can separate the soil from the stone. It keeps the stone from sinking into the soil over time.
Excavation makes room for the base
Excavation removes the topsoil and the old surface. It digs deep enough to fit the planned base and surface. Then the bottom gets a slope, so water drains toward the street or toward a drain.
The crushed stone base carries the weight
The base takes the weight of the vehicles and spreads it over the native soil. You build it with crushed stone, because its angular pieces lock together once compacted. Water also drains better between these pieces than through soil. The stone goes down in layers. Each layer gets a pass with a plate compactor or a roller before the next one. The thickness of the base depends on the soil and on how you use the driveway. A truck or an RV needs a stronger base than an everyday car.
The surface takes the wheels and the snow
The surface is the only layer you will see every day. Asphalt goes down hot on the base, then a roller compacts it before it cools. Interlocking pavers sit on a layer of sand or stone dust, spread flat. Sand then fills the joints, and a curb holds the pavers in place along the sides. A natural stone walkway or steps need the same solid base.
Why a driveway breaks down
When a driveway breaks down, the cause is often under the surface. You usually find one of these problems:
- a base that is too thin or poorly compacted, which settles under the wheels
- soft soil left under the stone
- water that stays under the driveway and freezes in winter
Redoing only the surface hides the problem for a while. We fix what is under the surface first, then redo the surface.