[CuLayTur]

Hello... I am building 2 different boulder wall at at my home and I have a question is someone can help.

For the first wall, I'm constructing a wall in the center of a circular driveway with 5" - 12" granite boulders, dry stacked about 2 ft heigh and 107 ft long.

The second wall runs the length of my home, with 18 - 24" boulders(dry stacked) about 3 ft heigh and 200 ft long.

I have build concrete block (pavestone walls) before and set a good 6" level compacted base, with drain pipe and fabric with 3/4" rock behind the wall.

But do I need to do the samething for the boulder walls. (base,drain and drain rock). I would think with the non-exact fitting of the dry stacked rocks, water would just run out of the seams and the 3/4" drain rock could also come out.



Thank You for your help,

Curt

[HRLand]

I'll be doing a similar job soon and have the same questions.

What I see around here is the voids left between boulders are filled with smaller stones but there must be some fabric behind them to keep the soil in place.

[Stonehenge]

The way that we install walls like that, once they get over 2-3' in height, is fabric completely enveloping the crushed stone behind the wall. That means fabric immediately behind the stone, fabric between crushed stone and soil. The fabric is usually dark enough that the little voids between stones isn't really noticeable.

If the wall is smaller, say 2' and under, we don't use any crushed stone at all behind the wall - my thought it - those voids are big enough weep holes to allow water to drain.

[Will Pacala]

Will you be putting in any plants or trees in behind or infront of this wall?? If so you might want to consider adding the fabric. The roots from these trees and/or shrubs can lift or seperate even move the wall and it's stones. Ive seen it happen before and it really is hard to fix.

[CuLayTur]

Thanks for the reply's. For the smaller driveway island, the idea was to plant grass ontop, with a couple of tree's in the center... But knowing the wife, she may in the future, want to place flowers along the top of the boulders..

As for the larger boulder wall, there will just be grass upto the boulders, the other parts of the yard will have more scrubs and bushs.. I think for the larger wall I will be using the drainage like you all suggested, with an envelope of crushed stone in Geotex fabric and drainpipe, this would definitely help.



Thanks,
Curt