Advice for gravel drive?

[JimS]

Located near St. Louis and needing to extend a spur off a gravel drive for a new detached garage/shop. Planning 10' wide and run is about 200'. Soil has a fair amount of clay. Current drive is CA6 which is common around here. Think it is basically 3/4 minus crushed limestone. Current drive is just CA6 as far as I can remember (no bigger base that I can recall. It has held up pretty well over the 15 years and needs some surface rock every 5 years or so.

Talking to contractors for the road I am getting recommendations all over the place. 8" thickness of CA6 from one - seems like a lot. Fabric and large base with smaller clean rock on top to keep the weeds out (which is a bit of an issue but not terrible. I have been adding clean rock on top but it doesn't pack as well). Some claimed the fabric would work its way up especially on the corners. Doing the large base seems like a good idea but it can work its way up sometimes.

The drive may get moved in a few years so am leaning to just using CA6 or maybe clean 3/4 rock.

I don't expect much heavy truck traffic after the initial concrete trucks and construction equipment. I only get a few significant deliveries a year and then it is usually a box truck rather than a huge one. How much radius is reasonable for turn for smaller trucks? I have a 90 degree turn off the existing drive.

I have a Kubota L3600 with loader and considered cutting the turf out myself so I would just have rock to be delivered. But may have someone else do it all.

Looking for advice on road material and thickness.

 

[EddieWalker]

Most important rule of any road or driveway is how you deal with water. Do you need a culvert? Is the road built up enough to allow water to run off of it and away from it? Do you need to ditch the sides of the road to carry the water away?

City and Country roads in my area build up the roads with clay that is highly compacted, then they put down a layer of crushed limestone. From what I can tell, County roads tend to be 4 to six inches this of stone, but right now they are working on access roads to Interstate 20 and it's easily 8 inches thick. Clay compacts so well here that fabric isn't needed. It doesn't hurt to have it, but it's an extra expense that can be avoided with proper dirt work. Using large stone for a base will help with soft areas, but they will always be an issue if the water that makes that area soft isn't corrected.

A few years ago my supplier suggested that I try crushed concrete instead of limestone. Cost is the same for either, but he said that it will compact better. I didn't really understand this, but gave it a try on his recommendation. The difference is significant. Crushed concrete remains rock solid no matter how much rain we get. The limestone will have a soft feet to it after long extended heavy rains that sometimes happen here almost daily in the spring time. You can feel the difference when you walk or drive over either materials, the crushed concrete is more solid.

 

[JerryK]

I did my drive mostly on native topsoils [ gravel/sand/clay ] by covering with pit run gravel and clay mix. I went over a foot to get elevation to keep water off it, with a couple 8" steel pipe culverts to move water from the high side of the drive to the lower. Packed that down real good and covered with limestone [ get it from Afton Michigan, and they call it Afton stone ]. Once it all compacted down it makes a great drive. Did not use fabric, fabric is great if you can keep it covered forever. Merry Christmas ... !!!!!!!!!!!!!!!!!

 

[Fallon]

Most important rule of any road or driveway is how you deal with water. Do you need a culvert? Is the road built up enough to allow water to run off of it and away from it? Do you need to ditch the sides of the road to carry the water away?

City and Country roads in my area build up the roads with clay that is highly compacted, then they put down a layer of crushed limestone. From what I can tell, County roads tend to be 4 to six inches this of stone, but right now they are working on access roads to Interstate 20 and it's easily 8 inches thick. Clay compacts so well here that fabric isn't needed. It doesn't hurt to have it, but it's an extra expense that can be avoided with proper dirt work. Using large stone for a base will help with soft areas, but they will always be an issue if the water that makes that area soft isn't corrected.

A few years ago my supplier suggested that I try crushed concrete instead of limestone. Cost is the same for either, but he said that it will compact better. I didn't really understand this, but gave it a try on his recommendation. The difference is significant. Crushed concrete remains rock solid no matter how much rain we get. The limestone will have a soft feet to it after long extended heavy rains that sometimes happen here almost daily in the spring time. You can feel the difference when you walk or drive over either materials, the crushed concrete is more solid.

It depends... most of my recycled concrete is great, packed in well & all that. A couple loads are just crap. No fines in them & the material just keeps moving around like pea gravel.

I just redid half my driveway. Scraped off the little gravel. Scraped off 8" to a foot of clay. Graded it all perfectly so I got just a little slope away from the house. Geotextile (beefy landscape fabric that wont get destroyed like cheap landscape fabric) over pretty much all of it. Then a light layer of the old dirty rock followed by 8" or more of recycled concrete.

No water or mud issues at all now. The soft spot at the edge with the crap concrete still needs fines. And as its settled it isnt perfectly graded or smooth now. I was kind of expecting that as I didnt have a compactor. I'll just do a final grade & smoothing on it here when I have time. Need to do the other half of the driveway next anyway.

As others noted the key is to get water off the road. Crown or slope the road, ditches & culverts on the side. Geotextile keeps the rock from sinking into the mud.

 

[jaxs]

+1 about good drainage,build drive up 3x as tall with clay as you want it to be after 3 years. The longer you wait while rain and trafic pack's clay,the better. Crushed concrete with fines is as good as I've found dollar for dollar. Recycled asphalt is also a good affordable material. If you hate weeds and grass on the drive,just spray as needed rather than desighning to prevent them. About the dumbest thing one can do is grade an otherwise smooth and stable drive just to kill weeds. Remember,build it up much taller than you want it to be perminatly.

 

[ovrszd]

I didn't want my drive elevated in front of my new shop/house. I removed the sod, added clay to get a slightly lower than surrounding area elevation. Then graveled with 2" clean crushed limestone. Once I got it stuck down I added a layer of 1 1/4" and down. It's still just a little rough but that'll disappear in another six months or so. Built the drive last Spring. It has just enough fall to drain. No drop offs or rises above the lawn. Easy to maintain.

 

[TractorGuy]

I did our road with crushed concrete a couple years back and it's holding up great. Our county agent recommended it over limestone and said the compaction rate was 200% higher than limestone. The stuff I bought was graded to be no larger than 3/4". I was skeptical after having a bad experience with concrete washout years ago but the crushed is the cats meow. DO NOT USE CONCRETE WASHOUT. Messy dusty stuff.

 

[Fallon]

While I'm a fan of recycled concrete I'm really against recycled asphalt. Generally its worn out when its torn out. It's relatively fine material compared to roadbase or recycled concrete & doesn't pack in well.

The stuff that does pack in well due to the binders not being worn out is splotchy. You'll get some parts that are hard & can't be maintained mixed in with potholes & areas that move around. The county ran into that on our dirt road. You could see where the grader tried to fix all the potholes & issues but just made some scrape marks on the hard bits.

 

[ruffdog]

Around here, a driveway that you can drive a truck (propane/septic/emergency) when it gets gooey, like when the frost is coming out, demands a good base. That means digging out the soil and clay so you can put a good layer of 4" crushed limestone (yes, the big stuff). Then you top it off with some 3/4 and fines. The excavator dug out about 12" for my drive but for a shed, I would say 6" would be minimum. If you don't get a good base in there, it's real tough to redo it later. We also have weight limits on our roads during the time the frost is coming out just for this reason. Some of our OLD roads do NOT have a good base either.

 

[Egon]

Clay is a preferred material for the base road.