Boulder wall

[Builder]

Customer asked me to build a simple, economical, stacked boulder wall to retain ~4' of fill dirt for a large garden. It's about 120' long. As you all know, odd shaped boulders don't stack real well. I trucked in about 15 loads of 24"-48" boulders.
I started out by skimming off a level ledge for the first courses to sit on. I doubled/tripled up on the 2 bottom courses so the next course will stack on top without falling off. Looks more like a boulder "berm" than a wall. Second/3rd course is more challenging.

Would you use fabric behind the wall to keep dirt/mud from coming through the front openings left because the walls are not perfectly sealed? I was also considering a 3" stone vertical layer behind the fabric, then folding the fabric over the top and behind the 3" stone, but cost/complexity is of concern. Can't get too carried away on perfection-it's not supposed to be a work of art, or cost like a work of art. However, don't want smaller rocks being pushed off or mud oozing through.

I'm more used to building stone/mortar or interlocking block wall with proper pipe/drainage behind it. This thing looks like it might be a problem in the future.

 

[beenthere]

Are you just part way along? Finished?
As to an answer to your questions (good questions), not easy to say without a better feeling for the situation....pics would help.

 

[Builder]

'bout 3/5ths done. No backfill yet. Still have time for fabric, stone...

I have access to some old 3" driveway stone. Not perfectly clean, but good enough. Fabric will be ~$200, so I will be doing them, just wanted to run it by someone else who's "been there" LOL

 

[Toyboy]

Yep, use fabric. They did on mine to keep the dirt from channeling through.

 

[dave1949]

I have several stacked boulder walls. One is about 5' tall. They all have fabric but no stone behind them. We have fine, silty soil and have never had any wash out between the boulders. I wish I had flat rocks, but Maine is mostly blessed with rounded glacial rocks. My rocks are anywhere from 1' to 4' and don't fit tightly at all.
Dave.

 

[Builder]

I have several stacked boulder walls. One is about 5' tall. They all have fabric but no stone behind them. We have fine, silty soil and have never had any wash out between the boulders. I wish I had flat rocks, but Maine is mostly blessed with rounded glacial rocks. My rocks are anywhere from 1' to 4' and don't fit tightly at all.
Dave.

Crazy question, but got any pictures of them? That sounds like exactly what I'm building.

 

[dave1949]

Crazy question, but got any pictures of them? That sounds like exactly what I'm building.

Here are some pics. Not really liking this wall. Might build a terraced patio there someday. This is the top of the wall.
Dave.

These were all put up in 2006.

 

[dave1949]

Builder:

1st pic is front of wall in previous post.
2nd pic is a wall I hand stacked but quick and dirty.
3rd pic is another large rock wall with flatter rocks.

Dave.

 

[Builder]

Thanks for the pics! :thumbsup: The 1st & 3rd pics are very similar to what I'm building. I can't stop thinking the one I'm building's just going to fall apart in a couple years but they seem to hold.

So you put fabric behind your's?

 

[dave1949]

Thanks for the pics! :thumbsup: The 1st & 3rd pics are very similar to what I'm building. I can't stop thinking the one I'm building's just going to fall apart in a couple years but they seem to hold.

So you put fabric behind your's?

Yep, fabric up against the undisturbed soil face, then the rocks were stacked up. They have been very stable so far. The were built on undisturbed soil too. The one with round rocks has been buried with snow from clearing the drive with the FEL every winter. So much open space within the wall, moisture never collects anyways. They do have a slight backward slant.

I wish we had more large flat rocks to work with, the round ones will never look very finished IMO. All the rocks came from our clearing and house excavation into a sloped bank. Of course, I'll never move them with my TC40, so someday the excavator will be back if I decide to redo that wall in something more attractive.
Dave.

 

[Builder]

Thanks, I appreciate the useful info & pics! :thumbsup:

 

[dave1949]

Thanks, I appreciate the useful info & pics! :thumbsup:

You are very welcome, hope the job goes well.
Dave.

 

[PA hayseed]

Builder, you do not have to use any type of fabric behind a stone wall. Drystone built retaining walls use "packing" as the material behind the wall, and it is very important on how you lay the packing in. No footers are required, just remove the vegetation and start placing the boulders on the bottom, add a little batter to the wall, and cope the tops. You are supposed to pack as you go, not after the fact. This is how stone masons have been building walls for centuries.

Now, I built a stone retaining wall at my house, and I packed behind some of it, and put 2b gravel in there for drainage. No fabric whatsoever, and since last year no silt, dirt, or debris has flowed out of my wall and the water didn't go into my basement.

Drystone conservancy has some ideas you can use, and they have classes you can go to. I went to one last year and helped rebuild a retaining wall. The only thing I didn't like about the class is that you pay to attend and then bust your butt for two-three days.

Here are some helpful links: Dry Stone Conservancy :: Welcome http://www.tutorials.com/07/0741/0741.asp
Dry Stone Walling Association - Dry Stone Walling Association of Great Britain

good luck! Nothing easy about boulders.

 

[PA hayseed]

Builder, you do not have to use any type of fabric behind a stone wall. Drystone built retaining walls use "packing" as the material behind the wall, and it is very important on how you lay the packing in. No footers are required, just remove the vegetation and start placing the boulders on the bottom, add a little batter to the wall, and cope the tops. You are supposed to pack as you go, not after the fact. This is how stone masons have been building walls for centuries.

Now, I built a stone retaining wall at my house, and I packed behind some of it, and put 2b gravel in there for drainage. No fabric whatsoever, and since last year no silt, dirt, or debris has flowed out of my wall and the water didn't go into my basement.

Drystone conservancy has some ideas you can use, and they have classes you can go to. I went to one last year and helped rebuild a retaining wall. The only thing I didn't like about the class is that you pay to attend and then bust your butt for two-three days.

Here are some helpful links: Dry Stone Conservancy :: Welcome http://www.tutorials.com/07/0741/0741.asp
Dry Stone Walling Association - Dry Stone Walling Association of Great Britain

good luck! Nothing easy about boulders.

 

[BX2230Dude]

This is a rock wall I built in 2004 and it's still standing. One of my first projects with the BX2230. 31,000 lbs of rock. I didn't use any fabric. Just stacked the rocks and backfilled with the dirt I cut out of the hillside. It's a little over waist-high on the highest end.

 

[MarkV]

This is a rock wall I built in 2004 and it's still standing. One of my first projects with the BX2230. 31,000 lbs of rock. I didn't use any fabric. Just stacked the rocks and backfilled with the dirt I cut out of the hillside. It's a little over waist-high on the highest end.

Doesn't look like it would be a good idea to stay at the Pub to long and mess up on your drive there, BXDude. :shocked::shocked:

MarkV

 

[BX2230Dude]

Doesn't look like it would be a good idea to stay at the Pub to long and mess up on your drive there, BXDude. :shocked::shocked:

MarkV

Good point Mark. If you're lucky you'll hit the rock wall, maybe knock out a few rocks and come to a stop. If you're un-lucky you'll go over the shear drop off on the right. The single row of rocks on the right is supposed to prevent that from happening.

Actually this is the beginning of my neighbor's property. The rock wall straddles the property line with about 75% being on my side. I paid about $500 for the rock (almost half of that was delivery). The neighbors offered to pay their share but I told them "forget about it", the additional seat-time was payment enough. We're both pretty happy with how it turned out. It's prevented the hillside from washing out and covering the driveway in mud for six years now.

 

[CurlyDave]

With rock retaining walls, I have always built and backfilled alternately.

Put down a course of stone, backfill to the height of that course. Set the next course back about half a stone width and after completing that course, backfill again. If you build the stone "wall" first you end up using much more stone, making a stone berm as you describe. No need for that much stone, no need for fabric.

I always turn the stones so the longest dimension is perpendicular to the wall. The wall is thicker and more stable this way.

 

[rbcsaver]

Builder, You leave out a lot of information, such as location, which has a lot of bearing... the wall's purpose, soil type, frost, freeze, heaving, rains, etc. I've built a number of stone walls, which have included some small boulders as well. Water will move "through" a stone/boulder wall, until it turns to ice, which will move the biggest "boulder." Is the wall'
purpose to hold back soil and re-direct water drainage, or just a decorative wall. So many questions and little info. HOWEVER, I always build mine in NE PA with 2B (driveway) stone base for drainage, some 2B stone at the wall base, inside the fabric, the 2B stone behind the fabric 1/2 or slightly more of the wall height, then soil. But we need more info.

http://www.tractorbynet.com/forums/projects/58265-splitting-rock-5.html#post1515165

Plus near done now......

Customer asked me to build a simple, economical, stacked boulder wall to retain ~4' of fill dirt for a large garden. It's about 120' long. As you all know, odd shaped boulders don't stack real well. I trucked in about 15 loads of 24"-48" boulders.
I started out by skimming off a level ledge for the first courses to sit on. I doubled/tripled up on the 2 bottom courses so the next course will stack on top without falling off. Looks more like a boulder "berm" than a wall. Second/3rd course is more challenging.

Would you use fabric behind the wall to keep dirt/mud from coming through the front openings left because the walls are not perfectly sealed? I was also considering a 3" stone vertical layer behind the fabric, then folding the fabric over the top and behind the 3" stone, but cost/complexity is of concern. Can't get too carried away on perfection-it's not supposed to be a work of art, or cost like a work of art. However, don't want smaller rocks being pushed off or mud oozing through.

I'm more used to building stone/mortar or interlocking block wall with proper pipe/drainage behind it. This thing looks like it might be a problem in the future.

 

[Builder]

Those little flat stacked stone walls are a totally different situation. Your's are very decorative. Mine is more functional. This one I'm doing is like a boulder "berm" stacked about 4' high. I took pictures, but need to post them up when I get some more time.