Your second consideration should be driveability. The driveway must provide safe, easy access for a motor vehicle from the road to the house (and back) in all weather. You’ll want space for two vehicles to pass each other at the entry, at the house end, and on blind curves (at least). Zoning regulations will stipulate the width of your driveway and its grade for a minimum distance beyond the curb cut. A typical one-vehicle driveway is eight to 10 feet wide (12 feet is better) with a grade of no more than two percent at the entry—that is, rising no more than two feet in 100 feet of length—and a grade of no more than eight percent thereafter (and five percent is better). Unless you want to burn out your clutch, a maximum grade is 15 percent. Curves should be gradual—arcs of a circle with a radius of at least 24 feet. A 48-foot turning radius is better (and essential if you want a moving van or UPS truck to get in and out). To read more follow the link below http://www.motherearthnews.com/diy/build-a-driveway-zmaz92aszshe