# Retaining wall for driveway extension



## NewHomeDIYGuy (Nov 23, 2011)

Hello guys,

Haven't been on here for a little bit but got a new project and could use the advice of those on here.

I'm looking to extend the existing asphalt driveway about 12' longer towards the rear yard keeping the existing width, but the ground has a slope to it towards the rear yard. I got a quote for doing the driveway extension, and they advised considering a retaining wall that way the extension would have a solid foundation. They do minor regrading and would bring in 21A for the base under the asphalt, but that's it. The issue is that they don't do retaining walls and I'd need to hire someone to do it.

The question then is what would be the best approach to tackling this problem? I'm thinking cinderblock and probably footers. Frost depth is 24" here. The wall doesn't need to be very high, maybe 2-3 feet above grade at the highest points in the corners, so I don't need to pull permits. I've seen some videos of people building small retaining walls without footers just by using proper backfill material but would this work? I'm a believer in doing things right the first time so want to plan it out ahead of time. I want hire someone to do the work since I don't have the time. It's a relatively small job in terms of retaining walls for contractors around here, so I know it might not be easy to find someone to do it.

For reference in the pictures, the existing driveway is about 20' from the chain link fence, so I'm looking to stop the driveway extension about 8' short. Do I have to be concerned with drainage for such a small retaining wall? Also, should the wall be built just past the end of the driveway or is it better to have it a foot or few farther? I've read about building retaining walls, but I'm not sure if it's different for a driveway with heavier loads. Little details like this I'm not sure about. 

The other question after the wall is built would be should I consider steps or just regrade the ground to the fence on a steeper slope? The concern w/ steps is it makes it harder to bring heavy equipment to/from the backyard if needed (like lawn mowers, etc).

I appreciate any and all advice. Thanks!


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## NewHomeDIYGuy (Nov 23, 2011)

To add, on further reading it looks like a "simple" segmental retaining wall can be made without footers, but simply using stacked blocks? I found this pdf: http://www.keystonewalls.com/media/Construction_details/3.ConsMan-Installation.pdf

Maybe I was overthinking it and concrete use is overkill. I guess frost heave is not a big concern with these types of walls either.


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## Fix'n it (Mar 12, 2012)

what about flattening that hill ? (looks like a hill in the pic)


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## Msradell (Sep 1, 2011)

The stacked block retaining walls are definitely your best bet. They are easy to do and hold up very well. They just rest on a gravel base instead of a poured concrete footer though they are also much less expensive to do. I would probably put steps down to the lower level but you could obviously put in a grass ramp if that's what you prefer.

Most of the manufacturers of the blocks have some very good instructions on their websites to help you decide how to do it.


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## Bondo (Dec 8, 2007)

Ayuh,... For that little bit of fall, just move the dirt/ lawn bank back,.....

The grass slope will just be 12' further back,....

Cheap, 'n easy,.... use the native soils already on site,....


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## NewHomeDIYGuy (Nov 23, 2011)

Fix'n it said:


> what about flattening that hill ? (looks like a hill in the pic)


As in just bringing in fill dirt and "moving" the hill back a little towards the gate? I'm not sure, I haven't thought about it, but I was/am concerned that I'd still have a problem w/ erosion or rather thought a retaining wall might be better.


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## NewHomeDIYGuy (Nov 23, 2011)

Bondo said:


> Ayuh,... For that little bit of fall, just move the dirt/ lawn bank back,.....
> 
> The grass slope will just be 12' further back,....
> 
> Cheap, 'n easy,.... use the native soils already on site,....


Thanks, I will definitely look into that option. I'll call a couple more asphalt companies and see if they can just do this at the same time. The one company said they'd to minor regrading, and have to remove ~7" for the asphalt and 21A base, so maybe someone can just regrade the area as well for a little extra $. Thanks a lot for all the advice! Worst case it's nice to know I could build a relatively simple retaining wall.


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## carpdad (Oct 11, 2010)

Asphalt driveways are more often floating than locked-such as basement slab. The driveway base should be compacted against something that's not going to give too much, but concrete footing and wall would be overkill. You may not want to regrade if it creates a sharp hump or want the whole drive to drain to the street.


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## NewHomeDIYGuy (Nov 23, 2011)

carpdad said:


> Asphalt driveways are more often floating than locked-such as basement slab. The driveway base should be compacted against something that's not going to give too much, but concrete footing and wall would be overkill. You may not want to regrade if it creates a sharp hump or want the whole drive to drain to the street.


That's been my concern about regrading, but maybe a small wall at the lowest point at the corner away from the house and regrading will do the trick. I'll go out there later today and look exactly how high up the base will need to be built up in the lowest spot (which is the left side away from the house). Maybe a corner wall 2 or 3 courses high that's covered with dirt in that corner would provide enough support for the compacted base rather than a full wall the whole width of the driveway. It's something I could do myself as well.

It's not clear in the picture, but the driveway currently has a slope to it that drains away from the house, not towards the street. I would keep that grade with the extension.


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## Colbyt (Jan 27, 2014)

Pictures tend to distort measurements. The fence looks real close to the drive in the first and a long way from the drive in the second.

Assuming you have about 20 feet from existing edge to the fence, I would do what Bondo said. Excavate, haul in rock fill and base for the drive, then use the soil to regrade the yard at about the same grade it is now. If the contractor hauls in enough rock and compacts it well to support the drive a foot of dirt added to the top will grow all the grass you want to mow. Bobcats and crushed rock is a lot easier on your back than building a wall.

Walls subject to vehicle traffic require a good bit more work and fill than simple garden walls. They tend to bow out and blow over with time.


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## NewHomeDIYGuy (Nov 23, 2011)

Thanks everyone for the suggestions. I had someone come by for an estimate and he suggested the best thing is to largely keep the existing slope/grade and not mess w/ making the driveway completely flat. They will bring it up 1' by using 12"s of 21A under the whole extension (there's currently about a 24" drop from the lowest point in the corner to the existing driveway grade) and do some slight regrading around the extension, but keep some slope. This way there won't be a sharp dropoff and I won't need a full on retaining wall. It also means I won't need steps and bringing equipment into the rear yard won't be a problem.

I originally wanted to put a basketball hoop at the end of the driveway in front of the gate but they advised to just place it on the side by the fence and I think that's the best way. 

Thanks again for all the advice!


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## Fix'n it (Mar 12, 2012)

you do know = that it is requiered to post pics of the completed project ? 
(like i am one to talk :whistling2: )


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## NewHomeDIYGuy (Nov 23, 2011)

Fix'n it said:


> you do know = that it is requiered to post pics of the completed project ?
> (like i am one to talk :whistling2: )


Haha np, will do. I try to post pictures of my completed projects and usually do. It'll probably be 2-3 weeks till it gets done but I'll post pictures when it's done. Thanks again for the advice. :thumbsup:


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## Colbyt (Jan 27, 2014)

Maybe a few during ones also. The older I get the more I love to watch other people work.


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## NewHomeDIYGuy (Nov 23, 2011)

Well had the extension done and the guy/company did a good job (I'll get a cpl pictures up tmw). Basically they brought in a whole lot of base material to do some regrading, compacted it, and laid the asphalt. They kept some of the slope which makes a retaining wall unnecessary and I don't need steps to the gate.

Only minor headache is that they broke a dryer vent that vented on the side, and now I need to get it fixed/replaced. I've personally never dealt with siding myself and I can't see how it attaches to the wall. I'm afraid I'm going to have to remove the siding to remove it as there are no visible screws. We'll see what the guy says tomorrow about it.


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## JamesCE (Nov 17, 2014)

NewHomeDIYGuy said:


> Well had the extension done and the guy/company did a good job (I'll get a cpl pictures up tmw). Basically they brought in a whole lot of base material to do some regrading, compacted it, and laid the asphalt. They kept some of the slope which makes a retaining wall unnecessary and I don't need steps to the gate.
> 
> Only minor headache is that they broke a dryer vent that vented on the side, and now I need to get it fixed/replaced. I've personally never dealt with siding myself and I can't see how it attaches to the wall. I'm afraid I'm going to have to remove the siding to remove it as there are no visible screws. We'll see what the guy says tomorrow about it.


still waiting on those pictures :smile:


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## NewHomeDIYGuy (Nov 23, 2011)

JamesCE said:


> still waiting on those pictures :smile:


My apologies, I hate it when others don't come back and post pictures and I'm guilty of that.. :biggrin2: 

I do have some video footage from a security camera that I wanted to get a few screen captures of to post here (they used a couple dump trucks of 21A) but I've been busy as munchkin #2 was delivered on the day the extension was done and it keeping us busy along w/ #1 so I don't know if I'll ever get around to it. Regarding the work, they laid a very good compacted base that extends ~1' beyond the new paved surface.

Also, I re-layed all the sod out and put some topsoil down (these pictures are pre-topsoil being laid) since they kind of did a sloppy job of it, but I wasn't expecting them to be landscapers. All in all looks good and nice to have more parking w/o blocking the garage. Slope isn't too bad and make bringing stuff into the back no problemo. The vent was fixed pretty quickly. It was a pretty easy fix and next time I'll just DIY it.


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## Colbyt (Jan 27, 2014)

Looks like it turned out well and with no wall that requires edging.


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## NewHomeDIYGuy (Nov 23, 2011)

Yep turned out well. Thx all! I've now started thinking/wondering about driveway sealing.. What's the general consensus, is it worth it? I know there's water and oil based. It seems like some say it's worthless but of course many driveway sealers say it's good for the asphalt..?


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## Bondo (Dec 8, 2007)

NewHomeDIYGuy said:


> Yep turned out well. Thx all! I've now started thinking/wondering about driveway sealing.. *What's the general consensus, is it worth it?* I know there's water and oil based. _It seems like some say it's worthless_ but of course many driveway sealers say it's good for the asphalt..?


Ayuh,.... I've been buildin' asphalt driveways for over 20 years now,...

I feel sealer is a bucket is good for pretty much one thing,...
To make it Black again,....

If ya got an ole driveway that's breakin' up, Maybe a coal tar sealer with sand in it, might buy ya some time,...
But, in many states, yer not trusted with coal tar anymore,...

Otherwise, a trick I learned almost 20 years ago, is to seal it with portland cement, right outa the bag,....

Ya take a drop-spreader, not a broadcaster, fill it with portland, then cover the driveway with a film of dry cement,....
If done on a very light rainy misty day, it'll hydrate, 'n leech into the pours, fissures, 'n popped rock voids, 'n of course Set-up,....
If it ain't a rainy day, fan it with yer hose to wet it, but not so much as to wash it away,....

Our world is built outa concrete, the portland binds the driveway the same way,....
Done annually, the driveway will last _Forever_,...

The only downside is, it's grey, not black,...
The Biggest Plus is, it isolates any petro-spills from attackin' the asphalt,....
A Gasoline drip will burn a hole through several inches of asphalt in a day, or less,...
The portland treatment, _Stops_ that,....

When I posted this here before it was asked 'bout paintin' it with black sealer after, for the color,...
I Wouldn't,....
I think the crap outa the can might hinder future portland treatments,....


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## Colbyt (Jan 27, 2014)

Don't apply anything until it whites out, that is 1-3 years. And then don't overdo it.


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## NewHomeDIYGuy (Nov 23, 2011)

Very interesting Bondo! 

Ya I've become skeptical of water based sealers and oil based like Gilsonite seem to have some very bad reviews by some people so it makes me wonder. The driveway is in good shape, and I'd like to keep it that way for as long as possible.. 

Very interesting regarding the portland cement. So you do this only when the driveway is looking rough? Fortunately I have no HOA so having a perfect black driveway isn't part of a checklist, but I also don't want it looking like an eye sore.  You have any pictures of what it looks like afterwards?


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## Bondo (Dec 8, 2007)

> So you do this only when the driveway is looking rough?


Nope annually startin' next Spring,....

Yer fresh blacktop will have cured, 'n the top most oil skin will be gone,...
In other words, it'll have greyed abit,...

I don't have any pictures, but have a couple commercial customers that do it,....
Most visible, 'n actually where I got this tidbit of info is the 1000 Islands Bait Shop at exit 49 on I-81 at the NY/ Canada border,....
The former owner taught me the trick,....
His original blacktop, 'round the gas pumps, lasted from the late '40s to the early '90s when by law it was required the pumps, 'n plumbin' be replaced, 'n concrete was used,....

If yer old enough to remember, before the '70s, a gas spill was a common occurrence at the gas pumps,...
an ounce here, an ounce there,.....
The portland protected the ole asphalt,....

Best description I can give ya for the Looks, is it'll look like concrete,.... Grey,...

The other guy runs an apiary, 'n uses skidsteers as forklifts,...
Nothin' will tear up blacktop quicker than a skidsteer, Loaded,....
I told 'im this tale the day We installed type 3 binder in his yard,....
He does the portland treatments annually,...

I was there last summer(3 years later), 'n nary a stone is outa place, nothin' torn up,...
Looks like a rock solid concrete lot, except with contours that blacktop allows that concrete is too hard to form that way,...


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## NewHomeDIYGuy (Nov 23, 2011)

Wow very cool! So the thing I wonder is it doesn't break up being such a thin layer of portland cement? I'd be concerned about it bonding as well to the asphalt..? I guess it breaks up little by little but regular annual re-applications keeps it solid? I will definitely look into it some more and think about doing this next year. I have a friend that has a concrete biz, I'll run it by him, curious to see what he says. 

My biggest concern is that it won't bond and just break off easily and look like crap, but I could certainly see it filling all the little ruts and grooves of the asphalt also and smoothing it out some..

I'm only in my mid 30's, but I do remember in the 80's oil spills being much more common than today. Thanks!


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## Bondo (Dec 8, 2007)

> Wow very cool! So the thing I wonder is it doesn't break up being such a thin layer of portland cement? I'd be concerned about it bonding as well to the asphalt..? I guess it breaks up little by little but regular annual re-applications keeps it solid? I will definitely look into it some more and think about doing this next year. I have a friend that has a concrete biz, I'll run it by him, curious to see what he says.
> 
> My biggest concern is that it won't bond and just break off easily and look like crap, but I could certainly see it filling all the little ruts and grooves of the asphalt also and smoothing it out some..


Ayuh,.... I think, yer thinkin' of a Much heavier coatin' than I am,....

The portland is dusted on, 'n flooded with water to wash the microscopic partials of portland to seep deep into the asphalt through cracks, 'n fissures to bond it together,...
The trick is to flood it, but not wash it away,...
Portland is heavier than water, 'n will seep through as deep as the water does,...
Like at the seam of yer old, 'n new driveway,...
It'll seep in, 'n help bond the joint together,...

Ya start with a grey asphalt driveway, 'n ya end with a grey asphalt driveway,....
In a short time, the tops of the stones ya could see before ya did it, you'll see again,...

Yer not trowelin' on a layer of portland,....


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