This information will help clarify and answer some questions.
Asphalt properties: Asphalt is a good surface for vehicle traffic. But its flexible-wear properties are subject to deterioration. If it isn’t maintained properly, expect cracks, lumps and potholes to develop.
To achieve a longer-lasting asphalt surface, request durable, coarser grades of asphalt.
One asphalt mix that works well for home driveways is called HL3A. Two inches of compacted asphalt is adequate for a home driveway; if a service professional suggests more than this, be sure he explains why.
Base content: Soil compaction is critical to ensure the pavement doesn’t buckle with time.
With dirt base you want to compress the soil as much as possible. A heavy roller should be used for small areas like sidewalks. Bigger equipment will be needed for larger areas like parking lots.
In warmer climates a compacted layer of road base (gravel mixed with dirt) followed with asphalt works best.
If you are adding asphalt over exsisting asphalt, you simply want to make sure that the area is free of debris (including rocks and as much dust as you can remove) to allow the asphalt to form a better hold.
Preparation: Preparing an area for paving is hard work and probably best left for professionals who have the expertise and equipment. Most will start by stripping the area of all vegetation, then excavating the area to the required depth. The depth (4 to 9 inches) depends on the climate and surface material. Next soil compaction is critical to ensure the pavement doesn’t buckle with time. In warmer climates, follow with a compacted layer of road base (gravel mixed with dirt) followed with asphalt. In colder climates, follow with full-depth asphalt.
Form work may be needed to build a set of stairs or maybe a wheelchair ramp.
Removing old paving: As far as old paving removal, you should check with your contractor to see if they know of places that buy old concrete and asphalt. Most types of paving can be recycled and used in new paving projects.
Check your grade: Also make sure and let your service professional know if there are steep grades or slopes involved in your asphalt project.