Gravel Driveway Construction, etc.

[selmore]

I'm preparing to construct a gravel driveway over rocky, clay soil. I have installed culverts and heard I need to backfill with compacting soil, then gravel. What should top surface(s) of driveway be and how deep? Thanks.

[Adron]

I had a long discussion with the excavator who built my driveway, and my neighbors. Basically he said to remove the top 4"-6" inches to get rid of all the grass roots, then put 2½" rocks to form a base. After those have been tamped in by driving on them for 6 months or so you follow that up with 2"-4" of base rock, drive on that awhile, and then a shallow layer of <3/4" final. I have followed his suggestions and am quite pleased with the result. Others may have better suggestions or have more experiance.

Good luck. Keep us posted.

[phxraptor]

Depends where you live and what stone is available. Here in Texas I follwed the same procedure useing limestone,the same stone that the county uses on the gravel roads we live on. Limestone will pack down and become almost concrete like when rained on several times and allowed to dry out betwen rains before any heavy traffic.

[Adron]

Yeah, sorry. The stone used was crushed limestone from a local quarry.

[bczoom]

selmore,

First, welcome to the forum.

I agree with what has been said so far.
Let me throw a couple more things out.

I would propose that you put down road cloth (it looks like the black silt fence used on construction sites but comes in wide widths) before putting down your stone. Clay in particular will allow the rocks to sink and the clay to move to the surface. The cloth will stop that. If you don't put it down, you may need to put more stone on every couple years.

Personally, I would go a bit deeper than 6". At 6" or less, any large truck that may come in may sink or cause deep ruts in the driveway, especially if the clay or whatever is below the stone is wet.

Brian

[Pat]

Yet another wrinkle in the fabric of space-time... I recommend you build up our roadway above the level of the surounding dirt. Even a couple inches will help but we went with aout 6 inches. We used some of the famous Oklahma red clay for that. and topped it with shale in chunks the size of yoiur fist and larger. This breaks down over time and becomes almose like a blacktop road. It withstands lots of rain and heavy traffic--- B U T --- you need to crown the roadway a bit to shed water and pay attention to repairing any areas that form water holding depressions as over time a clay base with standing water will get soft.

Any of the previous posters' methods can work well with a raised and crowned bed. I have concave swales that direct runoff that hold up under big delivery truks after 4 inches of rain BUT they don't hold water just let it pass.

The shale makes a better driveway than crushed limestone. I have both but used shale exclusively the last 150-200 feet next to the house. Less dust, more attractive look, doesn't "shed" so much and gets tracked into the house much much less.

[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]

[Slamfire]

All of the above but, if it is going to be a two track, the crown doesn't need to be very high, and can be on one side of the road or the middle depending on the drainage. .5 inch per foot is plenty for crowning.