Ok, we are just about to write an offer for a piece of land. To get to the building site, a portion of the drive will need to be pretty steep. Running perpendicular to the slope, the drive will rise 50′ over a 120′ run. Is a 24% slope too steep to get up in winter? How bad will the stone try to wash out? Looking at the topo, I believe I can run the drive parallel to the slope, but this will proably require me to dig out a ledge. Because of the steepness of the slope, the ledge will need to be cut into the hill with a retaining wall above or below. I’m concerned about the cost of excavation and there is a good possibility that we will hit limestone rock. It looks like we would need to put in around 220′ of ledge to get up the hill.
The driveway we would like to put in would be best described as unimproved. Rather than a strip of gravel, we would like to have two tracks (not ruts) in grass. When I talk to excavators, how do I best describe this? What do I want to put down for a construction base? The other drives that I’ve seen have used a 2-3″ crushed limestone for the base, and a 3/4″ crushed layer of TB on top of that. Can we just put dirt over the gravel base and seed it? Obviously the grass won’t live in the track, but it would give the look we desire. Do we need to dig out the dirt before putting the base course down?
I attached a .jpg suggesting how the drive could be put in parallel to the slope.
Certified boat fetish.
Replies
I had to cut my driveway into the hill and I still have a 10% grade. There are some people in the winter that have not been able to drive up our road after I plow it. 24% grade would have people spinning their wheels in the summer. If we get a real heavy rainstorm, I sometimes have to pull my gravel back up with the tractor and york rake.
Look for VaTom to reply to you. He is the master of sloped drives.
I think you need to seriously reconsider trying to buils on a 24% slope or verify that your numbers are correct.
Eric
[email protected]
It's Never Too Late To Become What You Might Have Been
I'm not trying to build on the slope. Just trying to get to a fairly level building site.
Certified boat fetish.
Edited 3/8/2006 7:45 pm ET by 1110d
I'm flattered. <blush>
But it's 'cause I spent $20k on my driveway almost 20 yrs ago and had to replace most of it. Mine ranged up to 30%, 4x4 whenever it rained. It rains here. Often. I got a very expensive education.
1110d, I took a peek at your topo, but didn't study it. Take a look at your numbers, they don't make sense. 50' rise in 120' isn't 24%. Even if it was, 24% is too steep to work for anything but asphalt. Trust me, I even tried highly textured concrete. Crushed stone is what my "professional" road builder sold me. Didn't work.
My conclusion was that anything over 15% is a mistake. My new driveway, rising 400' over 1/2 mile is 14% at most.
I'm currently working on a client driveway that briefly exceeds 15%, but that's due to a deeded ROW, which can't be changed. After dealing with drainage (rule #1), the finished surface is recycled asphalt.
A product you'll find interesting is grasspave (or gravelpave) http://www.invisiblestructures.com/GP2/grasspave.htm
I recently completed a commercial parking lot with gravelpave. But it was almost flat.
You need professional advice. Your topo is a start, but not a substitute for a survey. If you can find someone in your area, spend a few hundred bucks and save yourself some heartache. I've saved several around here. Beware of the guy who says he'll find your driveway by driving his crawler. You want to see measurement, and stakes. Rocket science it ain't, just expensive.
Good luck.PAHS Designer/Builder- Bury it!
Tom,I was on a driveway in King George County on Monday night that looked like a ski slope and I thought of you.On my egress, I had to back down because my truck lost traction on the gravel near the crest. The drive was straight down the slope, nothing to reduce the angle.I hope they know what they are in store for in the winter.
Jon Blakemore RappahannockINC.com Fredericksburg, VA
Jon, ski slope? Me?
Bunny slope maybe.
Went to see potential clients awhile back. Having heard about their driveway, I asked about 2x. "No problem, we get them all the time." Yeah, right.
I've got real tires on my van, and a little experience... Didn't make the last slope to their house, ~ 40%. Noticed a swale just downhill and swung into it so I could leave. He was shocked. Seems nobody else had ever had the presence of mind to back off the road, pointing downhill. Getting the tractor out was their normal routine.
Interesting way to live. Didn't take my driveway suggestion kindly. They hired the guy who screwed up mine originally. LMAO... I'm sure his estimate was lower.PAHS Designer/Builder- Bury it!
No, I meant that I thought of you in a good way, like "Tom would laugh at the guy who thinks this is acceptable"
Jon Blakemore RappahannockINC.com Fredericksburg, VA
Got it, Jon.
A few yrs ago I did a driveway in Rappahannock county (3 counties N. of here). Initially told the guy it was foolish to pay me to haul the machinery that far, find someone local. He sprang for a driveway survey, which showed that his preferred route was out of the question. Had to traverse the hill the other direction.
After that, he wasn't about to let anyone else touch it, even though with stakes laying it out it would have been difficult to screw up. I got the drainage right (rule #1), which is considerably more than simply an uphill ditch. 3/8 mile driveway that only needed 1 culvert. He didn't bother to gravel it for 3 yrs, even though he occasionally got his 2x BMW stuck after a rain. Would have been a great candidate for one of the grid systems. Probably ought to give him a call.
A major problem that I ran/run into is that Virginians don't live in places like these. Takes a transplant, like us. Roadbuilders here don't get the requisite experience. After my initial heartache, and before I finally figured out what to do with ours, I was wishing I'd imported a Colorado roadbuilder. Somebody who'd dealt with steep slopes and actually created an acceptable road to the top of a mountain before.
PAHS Designer/Builder- Bury it!
A major problem that I ran/run into is that Virginians don't live in places like these. Takes a transplant, like us. Roadbuilders here don't get the requisite experience.
I'd make a terrible road builder then. Where I grew up in IL the only question was "Do you want your driveway on the right or left?".
Jon Blakemore RappahannockINC.com Fredericksburg, VA
I'd make a terrible road builder then.
No worse than me. I didn't have any idea either, why I lost that $20k with the local roadbuilder. Got everybody I could find out to ask what to do. They all left, scratching their heads (or other parts).
In desperation I grabbed a 2x4, level, tape, and started measuring. Inclinometer's faster, but I got the job done. Which was determining how steep is too steep. Then I tried to lay out a new driveway (my first survey) with a lock level. Took 2 tries before it came out right.
Result was half the slope and a shorter driveway. Go figger...
Aren't you supposed to be working? I'm on hold, waiting for the Case dealer to figure out what they can do for me with the 580 hoe I brought down from your neighborhood. Got a wheel that's about to fall off. BTW, how did they manage to name a road there 666? Bugged the crap out of the guy I got the hoe from.PAHS Designer/Builder- Bury it!
Aren't you supposed to be working?
Yep, I am (sorta). Been working on Autocad, Quickbooks, and excel all day. Taking a break to rest my tired brain.
Where's SR 666? I have never noticed it.
Jon Blakemore RappahannockINC.com Fredericksburg, VA
Hoe came from NW of town. I didn't want to drag it through downtown. Guy took me NE of town to avoid it. Last fall, so I don't exactly remember. Intersects the 29 bypass.
Better you than me with those programs. I'll settle for a wheel falling off, stripped-out hub. Then I'm back to moving rocks. Tomorrow. PAHS Designer/Builder- Bury it!
The Rt. 29 Bypass, AFAIK, is a good distance from here. When you say "NW of town" are you referring to Fredericksburg?
Jon Blakemore RappahannockINC.com Fredericksburg, VA
Um, er, ahh... You might think someone would bother to read your signature line for location. But no, I was thinking Culpeper, which is where 666 is and the hoe came from. And has a 29 bypass, unlike Fredricksburg.
Sorry about that. PAHS Designer/Builder- Bury it!
Instead of trying to develop a 'spec' for your driveway, why not get referrals to a good excavator and ask for his recommendation? Have him come out and walk the site, then tell him what you want. A good guy with experience will figure out how to build it for you.
As far as I know a gravel drive should have a fairly deep base of 2" minus (that's the local material here). Water can flow thru it that way. The top is 5/8" minus. You could excavate the parallel tracks that you want, build up the base, and leave the grass strip in between.
It's going to be easier to excavate the total width of the drive rather than the tracks of the vehicle. Then it can be "crowned" properly also. You'll need switchbacks with a drive that steep.
Find out who does drives in your area. From the topo map certainly some of your neighbors have similar driveways. Unless you are talented with heavy equipment and have cheap access to said equipment, hire someone then listen to his advice.
The growth down the middle will come back on its own.
1110000
Uhm, yahno? 5:12 pitch is about a 42% slope.
10% slope is steep for a highway. A drive??.
I drew on your picture. If your pink trail is about 120', then the black hashmark is about 20' long in scale. The contour lines are 2' apart.
at 10%, the black hash will just fit between two contour lines.
I sketched in two ideas, but they wont work. They both cross too many contour lines in too short a distance. 8' rise in 4' of run a couple of times.
Another way to look at it. . .50' rise at 10% means a drive that is 500' long.
SamT
I gotta ask. Where in the world did you get this idea of having a driveway that just looks like grass?
Saw one somewhere?
There are formed concrete products that have holes through the blocks that permit grass to grow in driveways and parking areas. Maybe that is what you need. But I'll bet the expense will shock you.
You gonna live up there on that hill? Travel in and out once in a while on that driveway? Need milk or beer? You'll wear that grass down to the dirt in not too many trips and it'll look like a couple moonshiners live up there.
Get real. You need the assistance of a good local excavator that knows how to build driveways and roads.
Think hard. Maybe there is a reason that the land cost was so reasonable!
Where in the world did you get this idea of having a driveway that just looks like grass?
I believe the intention was two crushed stone tracks, surrounded by grass.
Maybe there is a reason that the land cost was so reasonable!
LOL... Yup, but my best real estate investments (including our land here) were always difficult access sites that most buyers couldn't fathom. I'm still looking for more, it's a great business plan. Driveway I'm currently working on I made the owners an offer at the first meeting. She was ready to jump, but they're old friends- and he got my joke. Would've returned at least 400% if they'd accepted.
Granted, with machinery and experience it's easier. I have passed on 2 properties in the recent past where a survey couldn't find a decent driveway. Always interesting to see what the next owner tries.PAHS Designer/Builder- Bury it!
BTW- your driveway is possible:View Image
Read about it here
Jon Blakemore
RappahannockINC.com Fredericksburg, VA
Ok, we have a bunch of clairifying here. First of all, the 24% slope was perpendicular to the slope. My sketch was parallel to the slope. The parallel run is 280' long and rises around 50' for a 16% average.
We also don't want a "grass" driveway. Just a pair of tracks worn through the grass. A ribbon of gravel just doesn't seem to fit this site. Also, the grass center should help hold the gravel in place. If I can keep the water from running down the tracks, that will help even more. It's when you have water flowing over the drive the gravel will move. This means I will need a ditch on the uphill side of the drive. The ditch will catch the water coming down the slope and keep it off the gravel. We'll fill the ditch with "native" rip rap to slow the water down.
I am familiar with the grass pavers, but I've never had a chance to use them. I know that the grass in the tracks won't take the traffic, but the pavers may help keep the stone in the tracks. Because of the duty cycle, I'd more inclined to use the concete version than plastic. This is actually a pretty good idea.
Jon-the link you provided to another thread doesn't work...
Certified boat fetish.
We have so many discussions about driveways, maybe we oughta start a FAQ about them. (-:I don't think 2 tracks is a good idea. It would be hard to stay on it, and hard to pass another vehicle. I've said this before several times, but it bears repeating: I'm sure you've heard the saying in real estate that the 3 most important things are location, location, and location. With gravel driveways the 3 most important things are drainage, drainage, and drainage. Sounds like you may already have a handle on that since you mentioned having a ditch on the uphill side of the drive. Putting down a a geo-textile mat is also a good move. I know a guy who put in a gravel drive in the late '70s and used the stuff. He claims he's never added gravel to the thing. I assume you have a fairly remote site, with difficult acces, but you're going to build on it? Keep in mind that you're going to have to get trucks in there to deliver stuff. It's almost a daily thing around here - We send trucks out to jobsites and they have no way to get 'em in. And paople get REALLY honked off that we can't get a semi through a 10' gate and up a muddy hill to their house.
Pentiums melt in your PC, not in your hand.
When you say "Geotextile fabric" are you reffering to the plastic mesh that they use for the concrete block retaining walls? It looks a bit like the plastic snow fence? Or the filter cloth used around drain tile?
Certified boat fetish.
I may not have the right name for the stuff - Can't remember exactly. Basically it's a fabric mesh that keeps the rock from sinking down into the dirt. Maybe someone else will jump in here who can tell you the correct name or give you a brand name....
Tommy Lasorda , Dodger manager, asked what terms Mexican-born pitching sensation Fernando Valenzuela might settle for in his upcoming contract negotiations: "He wants Texas back."
I may not have the right name for the stuff - Can't remember exactly. Basically it's a fabric mesh that keeps the rock from sinking down into the dirt.
Didn't IanDG have some stories about using carpet remnants for that very same purpose? I seem to remember him talking about getting it free from the carpet placese (the old carpet they were replacing).
jt8
"If you don't make mistakes, you aren't really trying." -- Coleman Hawking
Recent local code here prohibits building driveway over 20%, IIRC, due to concerns of safety, insurance issues, fire trucks access, etc. Also, heating oil trucks and LP gas trucks here always have to come up our hilly drive in reverse, I assume to facilitate an escape if problem arises reaching the top in winter...I love the hilltop views, but I dread maneuvering the hill on ice and snow. Even had problem finding snow plow guys willing to take on steep driveway.
" Even had problem finding snow plow guys willing to take on steep driveway."
I can tell you from experience that plowing snow on steep narrow roads is a serious pain in the kiester.
I remember Christmas Eve of 2004 in particular. I slid sideways down a hill in the middle of the night in the middle of nowhere.
Just slowly drifting down the hill, powerless to do anything. Wondering if I was going to end up in the road, in the ditch, or upside down in the creek I was sliding towards.
That'll put some pucker in yer cheeks......
"More hay, Trigger?"
"No thanks, Roy, I'm stuffed!"
1110 based on my experience.. you drive is too steep for anything other than concrete or asphalt...
anything else is going to present several problems already touched on
1: traction for the user vehicles
2: washouts and maintenance
..
owners who attempt this invariably wind up paving the dirve
Mike Smith Rhode Island : Design / Build / Repair / Restore
Looks like your attempting to install a driveway in Yosemite national park...I think I see El Capitan at the bottom!
Not that iknow much about drives, but what I do know is to check with the fire dept as to the max slope that they will drive up if there is ever a fire. I know of a previous client that couldn't get insurance on his home because the drive was too steep. Fire dept said all they would do is prevent the fire from spreading to other properties.
He had no problem getting a construction loan, but couldn't get his take out loan with out insurance.
Well only your excavator knows for sure.
The soil covering the hillside needs some sort of retainer to keep it from running over the surface of your gravel. The Geotextile Boss hog wrote of is a stronger version of that black plastic mesh used on most building sites as a filter to keep the dirt in place.
As for the base, "breaker run" whick is fist sized rock is the best base for most soils usually. But before you put it in you'll want to trench in your driveway drains and lighting runs cause after it is impacted by the truck traffic will make it impenetrable to the simple rental ditchwitch. Also spend a bit of time after the heavy traffic ends throwing the lost pieces back onto the driveway those loose stones in the lawn become crank benders to your lawnmower.
One thing is certain, you want to have the rock eventually covered by "traffic bond" which is crushed stone and fines no larger tha 3/4 inch. That packs down in std traffic. Otherwise you'll be a bobble head everytime you drive up to the house.
You will also need the overall roadway elevated a bit so the snow has a chance to blow off. in northern Wisconsin that helps.
As for the grass in the middle. Don't fret it will come. Just let your teenager cut the lawn & he'll blow enough clippings on the gravel to sprout up a lot of oilpan shiners to make your place look rustic.