Blacktop Preparation Questions

[jimb1724]

Hello All:

It's mud season in New Hampshire and I am seriously thinking about getting the top of my driveway blacktopped. It currently is soil with a heavy clay content which gets really messy this time of year, plus all year long dirt from shoes is constantly brought into the house... a real mess.

Anyway, I was thinking that I could do a lot of the site prep work myself, and I was hoping to get some input from those of you on this site that might have gone through the blacktop process before. The area to be done is about 35' wide and 60' long (2,100 sq/ft)... A picture of the area to done is attached.

So here are my questions:

what type of base material works best ? sand or screened dirt/gravel ?

how much of a base (depth) should be put down ?

since i am hoping to shape the parking area to direct water (rain/snow melt) should the base be level and shape the drainage with the blacktop ?or should I shape the base and just blacktop uniformly over it ?

any ideas as to the current cost per sq/ft of blacktop in the northeast ?

Any other thoughts and comments would certainly be appreciated as I have never approached a project like this before.

As always, thank you all for your input.

JIm

 

[GT2]

I prepped my area myself.
The paving contractor wanted 2" of 5/8" minus crushed rock, compacted.
I would think you would want your base at finish grade, as asphalt is ( or was ) very expensive.

 

[Egon]

The base preparation may depend on the amount of load you wish to it to support and the potential for it to become wet from the side hill in the background.

It should be dry before you start. Remove any organic materials from the present site and then grade to a slight slope to shed water. Packing will be of benefit. Then lay down some crushed gravel to a depth the wallet can stand and pack this gravel. Then you should be ready for the paving crew.

Have you considered concrete paving blocks? Over the long run they may be cheaper than the pavement and bad spots can be repaired.

Do you get frost heave in this area during winter months?

 

[CurlyDave]

I think your best course of action is to get bids from a few paving companies in the area.

At the time they come out ask the about prep work, what they usually do, how much less the bid would be if you did the prep, what the best possible prep over and above what they usually do might be, etc.

You may discover that you are going to save a minimal amount by doing you own prep, and, they won't warrant the work if you do the prep.

 

[ramoffroader]

Paving is like painting a car. The better the prep the better the end product. Remove a foot of material then put in your base stone work usually 6-8 inches. Top it with finer material 2-3 inches to pack it in and set your grade. Then put at least a 4-6 of black top on it. Even better is to put a 4 inch base/binder blacktop and 2-3 inch finish coat. Also put fabricate under the whole thing at the start. Expensive you bet it is. But was told this by my shop teacher once and never forgot." It takes half is long to do the job right the first time than it does to take it apart and do it over again".

 

[jdmar]

I think ramoff is right....sight prep IS the job. You may also want to look at concrete (check to see if it increases your taxes first). It may be cheaper than asphalt especially if you are going to stay there a while. Resale can be better too. I was able to get a large area done last summer/fall for the same cost per square foot that plain gray concrete cost me almost 8-10 years ago. People are really scrounging for work in my area though. The guy then stamped it for nothing but me paying for the dyes! I got darker dye and it melts the snow when sunny like fresh asphalt does. Deals are out there now.

I also agree with the paver stone idea. You will not save in prep work since they need a very well done base to support vehicles. But they are less likely than concrete to raise your tax. And they are about the same as concrete in price...if you put them down yourself. They can really increase the property value also. You can get relatively inexpensive ones that look great. You can also get some that lay in large "mats" like Cobble Systems does. Your large rectangle area makes them easier than lots of curves.

I doubt only 2" of small stone would really support things correctly. I again agree with ramoff. Dig it out, put geotextile, large stones (#2 or so..they are about 2.5"-4" around), then your #57 minus (about 1 1/4" to fines), compact VERY well. That is a lot of stone! Then put your asphalt or concrete down. Keep in mind what is #2 and #57 minus in my area may have a very different name where you are. (eg 503, 411, etc)

For pavers you would usually level with crushed limestone after the above prep, compact again. Then screed with sand before laying stones. Each manufacturer will give you good prep info for the pavers--listen to them not me if they differ!

Hard to estimate asphalt costs..that seems to vary a lot. Most areas I hear for concrete are still about $95 to $105 a yard for material now. You would need about 30 yards-- and that includes some extra and 4.5" thick. 26-27 yds would do it at 4" thick with little cuchion/extra. Labor varies massively. Hope some of this helps
Peter

 

[jimb1724]

Thanks Guys...

your ideas and suggestions are very much appreciated. definetly alot to consider.

i actually didn't even consider any type of concrete, as i thought it would be much more expensive.

i guess the best start would be to get both type of contractors up here to get some estimates and ask each one about their thoughts on my doing the prep work.

as always, thanks for all of the help. this is the most useful and friendly site on the web...

Jim

 

[pat32rf]

Between your clay base and heavy frost (its gonna go deep with no snow to insulate) you will need the same base for ashphalt that you would for a good gravel driveway if you want it to last more than 5-8yrs.. You could probably do a base for 6" of concrete a lot easier.
If you go pavers or similar you will need the same base as ashphalt as they won't spread the load much better than ashphalt whereas 6" of concrete with glass fibers will support/spread the load over a greater area so less base is needed.
We have the same hillside/clay/frost situation here in Bancroft (plus my son is in the ashphalt bussiness). The driveway actually heaves about 4-6" above the surrounding snow insulated lawn every winter until the frost is completely gone. Even with my price for asphault it would be a waste of time to try to do it. If I had a smaller area I would do concrete pads in the main walking/parking areas....