Your local municipal zoning and engineering departments
should be able to answer a few of your questions. They
certainly can comment on zoning specs. They may also
offer advice on whether you should "over-engineer" some
of the specs for your driveway.

Around here, it is very typical for the contractor to skim
off the old asphalt, topdress new aggregate in a few spots,
recompact the aggregrate, and lay down the new asphalt.

Often the original base wasn't up to spec and the inspectors
sometimes do a rather poor job of inspecting the crushed
stone before the new asphalt is applied. There seems to
be an attitude which assumes that "specs for the old base
and the new base haven't changed, we inspected it originally,
so we don't need to exert much effort inspecting the base
now." Whenever possible, I like to examine any new driveway
installation in our neighborhood, and I have observed many which
had as little as 1" of gravel in some portions of the base.

Price? You've got to get some folks out for estimates. The
cost is going to vary by local market. You may be able to
find some general guidelines on the Internet. There are free
construction cost estimators available online.

Advice? Get this work done during the hottest part of the
summer. You want that new asphalt to stay hot during
delivery, when being dumped, and during the entire rolling
process. The hotter the mix at the end of the job, the better
the driveway you will wind up with.

If you are skeptical, then try an experiment working with some
repair material (plaster, Bondo, fiberglass resin, etc.) which
starts off "plastic" and eventually sets up. Apply some to
a work surface, wait until it is nearly set up, and then continue
working (eg: smoothing) the material while it is finally setting up.
You will notice a very poor result in which there are many small,
localized areas of well bonded material. But those areas are
bonded to one another very poorly and the overall intergrity of
the work is severely compromised. The same thing happens
with asphalt which is allowed to cool too much while it is still
being worked. The driveway may look good, but it will have a
much shorter life.

More advice: Try to be around when the work is being performed.
You want to examine the bed of crushed stone and the compaction.
You'll want to confirm the thickness of the aggregate bed at multiple
spots prior to final compaction. You are doing that prior to compaction
so that you aren't disturbing the final gravel bed.

It is also helpful to watch the asphalt being applied and rolled. I
would seriously consider using a non-contact, laser-aimed thermometer
to monitor the surface temp of the asphalt as it is being applied
and rolled.

Observing other driveways being replaced gives you a lot of input,
and certainly you'll want to get references. It is obviously wise to
walk through the neighborhood and look at driveways which were
replaced 5-10 years ago, check out their condition now, and get the
names of the contractors.

Final advice: When getting estimates, check on the extra cost
of having an additional 2" of asphalt applied. Of course, this may not
always be practical if you are reusing the current gravel base. But,
in my opinion, it is a worthwhile option to consider in northern
climates, which are particularly rough on driveways.

Good luck,
Gideon

=============

Robert11 wrote

I posted this some time ago, but received only one reply with a suggested
Link, which doesn't work.

Thought I'd try again, as really hoping to get some info on.
It's such a big expense.
Thanks.
-------------------

Hello,

Have a home driveway that has to be repaved.

It's been so many years since it was last, I really don't remember any of
the details.

I believe a bed of crushed stone was put down first.

Questions:

a. Assuming there is a bed of crushed stones there now, do I want the
contractor to remove all this old stone, and put down a new stone bed before
putting
down the new asphalt ? Why ?

Or, can he just remove the old asphalt, and leave the stones in place ?
(seems almost impossible to do, I would think, but am not sure ?)

b. What should the stone bed thickness be ?

c. What should the asphalt thickness be ?

d. What's a "typical" price (per square foot, I guess) for a complete job
including the new stone bed ?
(live outside of Boston)

Not too sure what else to really ask.

Any other thoughts on would be most appreciated.