1 Also called tar and chip or oil and stone, macadam driveway can cost $1 -$3 or more a square foot on an existing driveway, or $600 -$1,800 for 12'x50'; and $2 -$4 or more a square foot for a completely new driveway with gravel base, or $1,200 -$2,400 for 12'x50'.