Hello,

Was just wondering about this.

It is pretty well accepted, apparently, that a new asphalt driveway for
a residence should be laid over about 4" to 6" of gravel.
Never over soil directly.

Why ?

The hot, liquid, asphalt I would pretty much think makes the gravel into
one, solid, "clump" underneath (the asphalt).
So, it's hard to see that any improved drainage results.

Increased "stability" perhaps ? If so, how ?

So what does the gravel add as a benefit over just laying the asphalt
on top of well compacted soil ?

Thanks,
Bob