All driveways need a certain amount of excavation and grading before laying asphalt, pouring concrete, installing interlocking pavers or installing road base.
How much grading and excavation each driveway needs varies from driveway to driveway greatly.
No two driveways are ever the same.
Two things need to happen for a good quality and solid driveway:
1) We want to make sure that the sub-grade is stable so the driveway is built on a solid foundation. A driveway is only as good as the subgrade beneath it. To learn more about the importance of subgrade preparation, be sure to read, "Should Base Be Installed Prior To Paving A Driveway with Asphalt?"
2) We want to make sure that the driveway grading is done so the water drains and sheds water properly.
It's vital that water runs away from the garage or home to avoid flooding, therefore the driveway needs to be graded to ensure drainage away from the house or garage.
We also want to make sure water runs off of the surface and doesn't pool or stand on the surface regardless of whether it's asphalt, concrete, interlocking pavers or gravel.
These two factors lead to the fact that most driveways require grading be performed. It would be a VERY rare occasion that a driveway would not need grading.
Believe it or not however, some contractors will put very little time into grading a driveway properly and the end result is you may wind with a problematic driveway that lasts half as long as it should, or even worse... a driveway that causes water to flood your home.
If you have a long and winding driveway leading up to your home, should the driveway be graded and paved with a crown, or should it be graded flat?
Grading a driveway with a crown is not recommended for a long driveway. The problem with a crown is when you drive on the driveway with your vehicle, the tires run on both sides of the crown, straddling the hump in the middle. This will cause asphalt, concrete or pavers to push outward on both sides… pulling away from the middle and cause cracks in the asphalt or concrete or openings between the pavers parallel with the driveway.
On gravel and road base driveways, the material just ends up on the sides of the driveway causing ruts and possibly a muddy mess.
Obviously, we want to minimize the cracking of a newly installed driveway as much as possible so grading the driveway and installing the asphalt, concrete or pavers flat, but also pitch it to one side or the other so the water will drain off is the right way to grade a long driveway. It doesn’t have to be a drastic pitch, but only about a 1/4 inch to 1/2 of an inch on either side. This will result in less maintenance and a much longer lasting driveway.
Keep in mind, on very rare occasions should a driveway be installed with a crown in it.
Crowning a driveway is actually a common rip off practice by the "fly by night" unethical contractors!
Here's a video we did explaining it.