[Pelican]

I'm faced with a job that I don't have a solid solution for. I've done quite a bit of work for this client this past fall and he has added a request to the project. His home is located on what I'll call a mountainside, I'm not sure the grounds actually meets the requirements of a mountain, but it's not far off.

Facing the home, on the right end of the house is a 2 car garage. To the right of the driveway and the house is an upward bank, at about a 7/12 pitch. The bank is formed by fairly soft shale, which has a thin coating of soil over much of it, exposed rock here and there.

What the client would like is a border about 10' away from the driveway, parallel to it about 110' long. A propane shelter is at one end and a dog pen at the other. He'd like decorative stone laid on the bank between the drive and proposed border.

I'm at a loss at what to do for the border. I've done quite a bit of block work here using Roman Pisa and ideally would build a low wall from the same material. The trouble is getting a solid level base to lay the block on. I've considered notching the shale with my cut off saw to yield a level shelf, but that will be real labor intensive.

Has anyone run into this before or have alternative ideas?

[4seasons]

what about bringing in one of those concrete guys with the walkbehind saws? might work alittle faster than your handheld.
and doing it like that would you cut deeper to acommodate some 411 limestone base?

[Matt Kulp]

How about a mid size excavator with a breaker. Break down to the depth you need for the base and excavate. This would be a heck of alot faster then the cut saw method.

[agla]

You could do a short dry laid garden border of similar stone to what is naturally there. Short enough to be not very significant, but high enough to be able to build up a gravel base for your wall to be on a couple of feet behind it. You could plant annuals/perennials to infill the area between the little dry laid border and your SRW without needing deep soil and give yourself the base that you need without killing yourself. Maybe your situation will allow that, or maybe not.

[Pelican]

I had discussed that idea with the client agla and he's receptive, my concern though is that the low rock wall will want to slide down the natural slope of the existing rock over time. Is there any way to compensate for that short of somehow cutting a level shelf in the rock?

[agla]

Do you have a picture?

[Corey]

could you drill holes, pound in rebar and pour a one side formed (down slope) footing?

[Pelican]

I'll try and get some pics tomorrow.

[agla]

I just reread the OP and see that he wants the wall 10' back. Can you make the front shale wall, or perhaps a short wall like the other wall, at the edge of the grass where it is flat so that you can build your base over the shale and build the grade in front of your wall to make it work?

How much higher does your base have to be than what is at the lawn (or driveway or walk) where the shale becomes a nonissue?

A low border wall even as high as 18" will compliment the taller wall without seeming big and intrusive.

[Pelican]

The stone will come to the edge of the driveway with no border there, just the asphalt. The border I need to build will separate the decorative stone from the woods behind it and uphill from the area. The problem is the angled and irregularly shaped shale that I have to build on. I forgot my camera today, will try again tomorrow.

[agla]

It would seem that there would be no problem right next to the driveway since they were able to build the driveway. If you build a short wall there it would allow you to place fill behind the wall and build a base over the shale without exposing the toe of the wall that you want to build 10' back. It may not work for a wall 10' back, but maybe you could bring that one forward a little bit as well.

Please excuse the cheesy diagram:

[Pelican]

Thanks agla!

You've got the layout down pretty close, but the objective is to just lay 3" of 1 1/4" decorative stone between the driveway and second wall. The stone will follow the natural slope. Where you've located the second wall is where I want to put a border to separate the stone from the woods. The border only needs to be about 6" high.

My concern is that the base you've shown will want to slide down the slope over time due to gravity and water load coming off the mountain. Have you had success with this situation?

[agla]

I have not built on this type of situation (I live on a sand bar and used to live on the Palouse - no rocks).

Are you saying that the wall that you want to build is only to be 6" high? If so, I would suggest that you use dry laid natural stone. It will look right without having to be precise like the Pisa wall. It will be much easier to chase the terrain that the shale has dealt you on the bottom and build it up to level with the varying stone than to try to force an artificial level base on top of it to build Pisa on. It will also be easy to make minor alterations to maintain it if/when it creeps on you.

[10west]

You could do meandering terraces with about 2 more steps in the terracing, with stones and larger boulder, picked for balancing like dimes, on edge, from large flat stones. I saw one, with giant flat boulders on edge, in places, and filler, smaller ones between. it was real natural, because the mason, let the top undulate naturally with the shape of each stone, then use trailing landcape plants.