[Will Pacala]

I happen to love using and working with any type of fieldstone. When a job came up I was very eager to get started. The plan called for a 34 foot wall with some assorted plants and a Laceleaf maple. I was talking to some other area contractors at the deli one day and he had said that he uses a mixtur of Quarry process and morter behind the walls for backfill. The idea struck me as sort of odd at the time but the more I think about it the more it would seem to work. On that project I still used the regular method of backfill. Do any of you use this QP and Morter process to backfill if so tell me if it works and how much morter to QP do you use. Thanks

[PSUscaper]

The only thing that bothers me with that idea is how does is handle drainage? QP by itself does not drain to well, and will hold water in the winter time exerting force on the wall and possibly causing it to fail.

By adding cement to it, you are basically pouring a solid wall. Solid walls tend to push over.....especially in this area.

I would think if you are going to go through the trouble of mixing QP and cement together(which would be a good amount of labor), you might as well just have a concrete truck come in and go all out.

I know masons that do pour concrete behind there dry laid walls......but most of the time they are very low walls.....less than 2 feet.

If you were to do this, I'd keep two main things in mind. First of all, install weep pipes in the walls that go through the wall and behind the QP/cement to relieve water pressure. Next, I would calculate the extra expense for doing this, and figure out whether or not customers are willing to spend that. You may find they are not.

steve

[Will Pacala]

Oh, I would never use this method for just the same reasons that you just said. The water would just freeze and crack the mortar and push the wall down. I would never do this process on a medium - large wall.

[Stonehenge]

I heard from our member down under (BJR) that they use a similar process. However, they can do that because it doesn't freeze.

Since you have freeze-thaw, I wouldn't be tempted to try this - it'll hold any water, and start pushing the wall over millimeter by millimeter.

And if the wall is really small, say 12-18", I'd just not use anything at all. That is to say, use whatever is there, soil, whatever. It shouldn't be enough to push a 12" deep wall over. Anything taller and you should start throwing clear stone behind it.

Just my $.02,

Jeff

[Will Pacala]

Even for the small walls, I still mix in some stones with the dirt for that added drainage.

[jwholden]

Never did a dry stack wall over 2', but if I did I would put some perf pipe behind it and backfill with 3/4 gravel. If I was really ambitious I might put a geotextile behind the gravel.

I'm building a VERY small (one pallet of stone) dry stack this week. Curious how it is going to come out.

[Will Pacala]

What type of backfill are you using if any and how long and tall is the wall?

[agla]

Do you guys install weep holes for drainage. Our guys use 1' poly sprinkler pipe. I'm noy sure of the spacing, but pretty often.

[Stonehenge]

I don't use weep holes for dry laid stone - I'm of the opinion that the gaps in the stone are sufficient for water to escape.

That being said, next week we are going to tackle a wall about 100' long, averaging 2' in height, and it will all be mortared. For that wall I intend to install 1/2" PVC every 8' of every course, along with perf pipe in crushed stone, to relieve any water pressure on this installation.

[jwholden]

Jeff,

Is that wall building next week going to look anything like the wall you built at your old house?

[Will Pacala]

What wall at his house? I never saw it.

[Stonehenge]

Very similar, but using thicker stone, and a much bigger wall. Also, it'll be without the lights.

Will, you can find pics of the small wall I built at my old house here

[Will Pacala]

Oh, cool, nice work especially that electrical work too. Did you do the wiring or did an expierinced electrician do it?

[Stonehenge]

Low voltage. We tackled it ourselves, as that's one of our offerings.

[Will Pacala]

Cool, that's a really good thing to offer it's really easy and if you do irrigation you might already have a good trencher.