The only concern I would have (my stone driveway is the same as yours-12" thick but has many yrs of dirt leaves etc.)would be the drainage of any h20 that might get into the base then expand when the temp falls and possibly 'heave the new driveway.I've talked to guys about paving mine general consenus is leave the sub-base in place and level the existing. If you can get 'millings' or 'rap' same product(recycled asphalt pavement) as someone said that would work. Sometimes contractors look for places to dump this product. In this day and age here in Pa. almost all rap goes back to the plant ot be added to new asphalt in proportion. I've never used rap but couple of friends-farmers say it does work. Generally-1 yd of concrete will cover 80 sq ft at 4" thick. I've never estmated asphalt. I would think 3" plus 1-1/2 top would work. There is in Pa. asphalt types-9.5 mm (the max stone size is 1/2"),19mm max stone size of 1",25mm-max stone size of 1-1/2". I know 1 guy who used 4" of 19mm for his drive and it is working(he is an aspahlt tech at a plant). One plant here the price for a ton of 25mm is 53.50,19mm is 50.50,9.5mm is 60.50. Coverage I'm not sure / ton.
|